Our DMF had covered around 180K and I fitted a new one with the clutch after the release bearing broke up, although there was a lot of rotational slack in the old DMF it didn't rattle so I think it could have carried on with a new clutch. The new DMF was only slightly better.
You don't need a hoist as the gearbox can be supported from the tie bar between the wings (later 807's did not have this) on a length of rope, then rotated and slid into the gap between sub frame and chassis leg. Remove the control plate on top of the gearbox to allow this. Make sure you tie the gear change cables well out of the way as they will get in the way when refitting the gearbox.