With the drivers side back wheel off the ground, watching the tailshaft while rocking the wheel back and forth so as not to make the shaft turn, is it normal to feel clunks and movement in the diff centre and there being maybe 1/6th of a turn of the wheel in free play? I understand there should be some play in the diff, but how much is normal and should I be able to feel clunks and stuff. Also, when you lift off the throttle while driving it clunks as well. Shagged??

unless it's whining or not working as it should i'd leave it well enough alone. one thing i've learnt with cars, particularly fords, if it ain't broke don't fix it. it only creates more problems.

clunk on back off could be anything from engine mounts to diff mounts. not enough information to decide. if the diff had no play it would constantly lock in and out. how much play is acceptable is a bit like asking how long a piece of string is without taking it apart and generally an expensive rebuild.

Just done the same test on my EL parts car, its infinately smoother and has about 20% of the play. The EB one feels like its full of gravel compared to the EL one. Ive already got the EL handbrake in the EB as with the rest of the EL lower dash and interior... what do I have to change to get the complete EL diff into the EB. Im guesing brake lines and thats about it??? Do they bolt up in the same places or are there a few nasties lurking in there? Failing swapping complete disc to disc assemblies, do the backing plates of the EL bolt to the EB housing without modification. The aims here are to have a diff that isnt f**k (I'll swap the centres over if I have to) and to have the EL drum in disc handbrake set up.