You remove the clamp numbered 16 on the schematic posted by jimmymarsbar and then all pipes and sensors attached to the exhaust.
It is probably easier to remove the entire exhaust from clamp 16 back as splitting the exhaust behind the cat/DPF unit can be quite difficult in situ as it is a socketed system which becomes quite corroded and difficult to separate over time. You might need heat and a lot of penetrating fluid to help separate it. If you hit the joint to help release the rust between the 2 pipe sections, use a wooden block between the hammer and pipe to prevent deformation of the pipe. If you dent the pipe socket system here with a hammer, it will make it virtually impossible to separate.
You must split it to clean the DPF unit however, you will not get a decent clean if you try to do it through the entire exhaust system.
Just for your info, here is the build sheet for the car [data overload...

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Vehicle family 307
Build code 09347 89 1 0044
Warranty Start Date 10/07/2002
Engine serial number 10 DYLX 4042939
Gearbox serial number 20 DM09 4629938
BER e2*98/14*0252*02
General information
PRODUCT TYPE CAR
COMMERCIAL MARQUE/COMPONENT TYPE PEUGEOT
VEHICLE FAMILY 307
SILHOUETTE 5 DOOR SALOON
TRIM LEVEL XS PACK
ENGINE DW10ATED TURBO DIESEL PARTICLE FILTER
TRANSMISSION BVM5
PAINT TYPE METALLIC PAINTWORK
BODY COLOUR EZR - PAINT ALUMINIUM GREY
INTERIOR TRIM TYPE PALASSARI CLOTH + "MU" EFKA
UPHOLSTERY COLOUR "FM"
GEARBOX (CHARACTERISTICS) BE4-5L MANUAL GEARBOX
ENGINE (TYPE) EW/DW
OTHER BADGE, " MISC. " WITHOUT FULLER BADGE
BADGE HDI
Vehicle characteristics
TRIM LEVEL XS PACK
PAINT TYPE METALLIC PAINTWORK
BODY COLOUR EZR - PAINT ALUMINIUM GREY
INTERIOR TRIM TYPE PALASSARI CLOTH + "MU" EFKA
UPHOLSTERY COLOUR "FM"
GEARBOX (CHARACTERISTICS) BE4-5L MANUAL GEARBOX
STEERING VARIABLE POWER STEERING
SPEEDOMETER DRIVE W/O TACHO TORQUE
Fuel supply-Engine
ENGINE DW10ATED TURBO DIESEL PARTICLE FILTER
DIESEL FILTER WATER DETECTOR WITHOUT DIESEL FILTER WATER DETECTOR
CYLINDER BLOCK (MATERIAL) CRANKCASE CAST IRON
FUEL DIESEL FUEL
EMISSIONS STANDARD (ENGINE) EEC 2000 DEPOLL (ENGINE)
ENGINE (TYPE) EW/DW
CATALYTIC CONVERTER 2-COMPONENT PLATINUM FILTER CATALYSER
OIL COOLER MNTG WATER/OIL EXCHANGER ON ENGINE
CRANKCASE GAS CIRCUIT HEATING W/O HEATER CASING GAS CIRCUIT
EOBD SELF-DIAGNOSIS SYSTEM WITHOUT "EOBD" AUTO-DIAGNOSTIC
DEVICE (ANTIPOLLUTION) "EGR" EXHAUST GAS RECYCLING
VEHICLE TECHNICAL DEPOLLUTION L4 VEHICLE TECHNICAL DEPOLLUTION
PARTICLE FILTER PARTICLE FILTER
FAN 1 FAN 2 SPEEDS IMPROVED 400W
FUEL VAPOUR RETRIEVAL WITHOUT PETROL VAPOUR RECUPERATION
INJECTION ASSOCIATED VARIANT MOUNTING BOSCH
HYBRID ENGINE WITHOUT ALTERNATOR-STARTER
TANK FILTER RESERVOIR FILTER INTERIOR
THROTTLE HOUSING (ENGINE INLET AIR CIRCUIT) WITHOUT THROTTLE HOUSING (INTAKE AIR ENGINE)
Gearbox Transmission
TRANSMISSION BVM5
GEARBOX (CHARACTERISTICS) BE4-5L MANUAL GEARBOX
FINAL DRIVE RATIO REAR AXLE HYPOID GEARSET 19 X 70
SPEEDOMETER DRIVE W/O TACHO TORQUE
WHEEL STYLE 16 INCH ARIANE ALLOY WHEEL WITH 5 OPENINGS
GEARBOX TYPE (TYPE APPROVAL) GEARBOX BE4/5 L TYPE
DIFFERENTIAL (GEARBOX) DIFFERENTIAL 70
TYRE (SIZE, TYPE) TYRE 205X55X16 V
WHEELS FITTED 6,5" RIM ROAD WHEELS
WHEEL (TYPE) ALLOY WHEELS
GEARBOX TYPE GEARBOX BE4R
Suspension-Steering-Brakes
ABS WITH ABS BRAKES
REAR ANTI-ROLL BAR REAR ANTI-ROLL BAR DIAM 26
STEERING VARIABLE POWER STEERING
FRONT ANTI-ROLL BAR FRONT ANTI-ROLL BAR DIAM 22
BRAKE TYPE VENTILATED FRONT DISCS/REAR DISCS
SUSPENSION NORMAL SUSPENSION
DYNAMIC STABILITY CONTROL SYSTEM ELECTRONIC STABILITY PROGRAM
BRAKE ASSOCIATED VARIANT ESP BOSCH 5 7
Body fittings
TOWBAR WITHOUT TOWBAR
HORNS HORNS-HARMONY
AERIAL SHORT ROOF AERIAL
SIDE MOULDINGS (TYPE) BODY COLOUR LATERAL PROTECTORS
SIDE MOULDINGS (DIMENSION) STANDARD LATERAL PROTECTORS
WHEEL EMBELLISHER (STYLE) APOLLO TYPE
REVERSING LAMPS WITH 1 REVERSING LAMP
ADDITIONAL SHIELD (UNDER ENGINE) W/O ENGINE UNDERSHELDING
EXT. REARVIEW MIRROR COMP. FUNCTION EXT MIRROR MANUAL-FOLD BACK
EXHAUST TAILPIPE TRIM W/O EXHAUST OUTLET EMBELLISHER
WINDSCREEN WIPER FRONT WIPER BLADE W/O RAIN SENSOR
REAR SCREEN WIPER REAR SCREEN WIPER
HEADLAMP WIPER W/O HEADLAMP WIPER
FRONT PANEL BLANK WITHOUT FRONT BUMPER PLUG
ROOF GLASS WITHOUT ROOF WINDOW
BUMPER BODY COLOUR STANDARD FRONT/REAR BUMPER
MUDFLAP WITHOUT REAR MUDGUARD
FRONT FOGLAMP NO FRONT FOG LIGHTS
EXTERIOR REAR VIEW MIRROR (DRIVER SIDE) DRIVER’S DOOR MIRROR ELECTRIC CONTROL
EXTERIOR REAR VIEW MIRROR (PASSENGER SIDE) PASS EXT RRVIEW MIRROR NON HEATED ELECT CNTRL
SPARE WHEEL STEEL WHEEL + STANDARD TYRE
EXTERIOR ACCESSORIES BODY COLOURED EXT HANDLE+FLAP TRIM+EXT MIRROR
REAR SCREEN WASH REAR SCREEN WASH
SUN ROOF FIXED ROOF
BUMPER TRIM BODY COLOUR BUMPER STRIP
GLASS (APPEARANCE) TINTED
REAR QUARTER WINDOW (TYPE) WITHOUT REAR QUARTER GLASS
WINDOW (TYPE) ACOUSTIC WINDSCREEN EXCEPT SINGAPORE
Interior fittings
INTERIOR TRIM TYPE PALASSARI CLOTH + "MU" EFKA
ANTI-THEFT ALARM WITHOUT THEFT PROTECTION ALARM
REAR HEAD RESTRAINT REAR HEADREST ADJUSTABLE
FRONT HEAD RESTRAINT JOINTED FRONT HEADREST
REAR SEAT SEPARATE FOLD BACK BENCH SEAT
SUPPLEMENTARY SEAT WITHOUT SUPPLEMENTARY SEAT POSITN
REAR SEAT ARMREST WITHOUT REAR ARMREST
LOAD FLOOR MOULDING WITHOUT LOAD FLOOR STRIP
LUGGAGE COVER WITH LUGGAGE COVER
REAR SEATBELT REAR 3-POINT 3 INERTIA REEL SEAT BELT
FRONT SEATBELT PYROTECHNIC SEAT BELT WITH ALARM
CLIMATE (AMBIENT TEMP) TEMPERATE COUNTRIES
SPEED GRADUATIONS GRADUATION MPH
RADIO EQUIPMENT FEED AERIAL RECEIV FRT SPEAKER TWT REAR SPEAKER
DRIVING POSITION RIGHT HAND DRIVE
ADDITIONAL HEATING AUTOMATIC ADDITIONAL HEATING
DASHBOARD EQUIPMENT STANDARD DASHBOARD + BRIGHT SILVER ALUMINIUM PANEL
INT. TRIM AND EQUIPMENT VARIATION STANDARD INTERIOR EQUIPMENT DRESSING
LOUDSPEAKER 4 FR SPEAKERS (2 TW + 2 FR) + 2 RR SPEAKERS
RADIO CONTROLS REMOTE RADIO CONTROL WITHOUT CD FUNCTION
SCREENING (BLIND, SIDE SUNBLIND, SUNROOF) WITHOUT REAR BLIND
FRONT PASSENGER SEAT HEIGHT CONTROL WITHOUT FRONT PASSENGER SEAT HEIGHT ADJUSTMENT
DRIVER SEAT ADJUSTMENT WITHOUT DRIVER’S LUMBER AND SIDE SUPPORTS
FRONT PASSENGER SEAT ADJUSTMENT WITHOUT PASSENGER’S SIDE AND LUMBAR SUPPORTS
DRIVER’S SEAT FOLDING W/O FOLDING DRIV FRONT SEATING
FRONT PASSENGER SEAT FOLDING W/O FOLDING PASS FRONT SEATING
FRONT SEAT ARMREST ASSEMBLY WITHOUT FRONT ELBOW REST
EXTERIOR TEMP. INDICATOR EXT TEMP INDICATOR
COMPACT DISC WITHOUT COMPACT DISC
STOWAGE BIN WITHOUT SETTING BOX
SATELLITE NAVIGATION SYSTEM WITHOUT NAVIGATION SYSTEM
REAR WINDOW LIFT MAN CTRL REAR WINDOW LIFTER
DRIVER’S WINDOW LIFT SEQUENTIAL DRIVER’S ELECTRIC WINDOW
PASSENGER’S WINDOW LIFT SEQUEN CONTROL PASSENG FRONT WINDOW LIFTER
DISPLAY DISPLAY (RADIO+CLOCK AND OR TEMP, CD)
COURTESY MIRROR DRIVER’S CONCEALABLE+PASS NON CONCEALABLE NO LIGHT
OIL GAUGE STD OIL LEVEL INDICATOR
FITTING REAR HEAD RESTRAINT MOUNT 3 REAR HEAD-REST
HEATING ELEMENT NON HEATED SEAT
FRONT LATERAL AIRBAG THORAX SIDE + CURTAIN AIRBAG
PASSENGER AIRBAG PASSENGER AIRBAG
ELECTRIC WINDOW (OPERATION) DRIVER + PASSENGER ELECTRIC WINDOW AUTO STOP
ON-BOARD COMPUTER NO COMPUTER
EQUIPMENT PACK W/O EQUIPMENT PACK
EXTERIOR REAR VIEW MIRROR (HEATED) HEATED DOOR MIRROR
AIRBAG DEACTIVATION MANUAL AIRBAG DEACTIVATION
INTERIOR DOOR CONTROL (APPEARANCE) SILVER EFFECT INTERIOR DOOR HANDLE
FRONT SEAT GUARD WITHOUT CAB PROTECTION PANEL
STORAGE (DRIVING POSITION) WITHOUT ROOF FRONT CONSOLE STORAGE
RADIO RECEIVER "RD3" RDS COMPACT DISC AUDIO SYSTEM
REFRIGERATION SINGLE AIR CONDITIONING
CRUISE CONTROL WITHOUT SPEED CONTROL
DRIVER’S SEAT HEIGHT CONTROL PARALLEL DRV HEIGHT ADJ
INTERIOR REAR VIEW MIRROR DAY -NIGHT INNER REAR MIRROR
DRIVER AIRBAG DRIVERS AIR BAG
LOAD SPACE STORAGE WITH BOOT TIDY
OBSTACLE DETECTION SYSTEM WITHOUT OBSTACLE DETECTOR
TRIM ADAPTATION GEAR LEVER KNOB CHROME INSERT
FLOOR MAT W/O CARPETMAT
EQUALISER AMPLIFIER WITHOUT EQUALISER AMPLIFIER
LOCKING CONTROL CENTRAL DEAD LOCKING
REAR QUARTER WINDOW (TYPE) WITHOUT REAR QUARTER GLASS
WINDOW (TYPE) ACOUSTIC WINDSCREEN EXCEPT SINGAPORE
STEERING WHEEL RUBBER STEERING WHEEL 3 BRANCH
FAN 1 FAN 2 SPEEDS IMPROVED 400W
RADIO-INFORMATION-COMMUNICATION PACK RADIO CD / INFO 2
DRIVER’S KNEE AIRBAG WITHOUT DRIVER’S KNEE AIRBAG
Electrical
ALTERNATOR ALTERNATOR 150 AMP
HORNS HORNS-HARMONY
BATTERY BATTERY L2 400
STARTER MOTOR STARTER MOTOR CL 5
SPECIAL LIGHTING WITHOUT PARTICULAR LIGHT
REVERSING LAMPS WITH 1 REVERSING LAMP
EXT. REARVIEW MIRROR COMP. FUNCTION EXT MIRROR MANUAL-FOLD BACK
MULTIPLEXING MULTIPLEXING ASSEMBLY CAN VAN
FRONT FOGLAMP NO FRONT FOG LIGHTS
Component manufacturers
BRAKE ASSOCIATED VARIANT ESP BOSCH 5 7
INJECTION ASSOCIATED VARIANT MOUNTING BOSCH
Miscellaneous
SPECIAL SPECIFICATION STANDARD
ATMOSPHERIC CONDITIONS NORMAL ATMOSPHERE
DRIVING POSITION RIGHT HAND DRIVE
RADIO HEADPHONE SOCKET WITHOUT ACCESSORIES SOCKET
TRAFFIC SIDE DRIVING ON THE LEFT-HAND SIDE
SIDE IMPACTS DOOR WITHOUT REINFORCEMENT
SET OF KEYS 2 HF PLIP KEYS
EMERGENCY EQUIPMENT W/O HELP EQUIPMENT
SURFACE CONDITIONS GOOD TERRAIN
EXTERIOR ACCESSORIES BODY COLOURED EXT HANDLE+FLAP TRIM+EXT MIRROR
SPEED MONITORING WITHOUT SPEED CHECK
SLAVE CONTROL UNIT BSI COMM 2000