[s-cars] Center drive shaft u-joint

[mlp on D530]

If my increasingly suspect memory serves me, sometime, long, long ago, in a
galaxy far, far away there was a thread on repairing or replacing a UrS4/6
center drive shaft U-joint with either a commonly available substitute
Mercedes Benz or BMW cross over part?

Any one recall the details; or part number; or a write up on SMJ's or
Charlie Smith's invaluable sites?  

It's not for me so much as poor Pizzo, who's now somewhat stranded in
Steamboat without the Green Garbage Can (P Krasusky's "GGC") to kick around
with the www.gruppe-q.com crowd.

Cheers
Mike