rear end clunk- any BTDT?

[J123fs at aol.com]

Hey all,
I have a nice clunk on the rear end of my V8. Pass side- mostly on rebound,  
like the shock mount was loose or broken spring- but, I have neither.
I replaced the rear traverse link (some might call it a upper control arm)  
as there was play in it. But after the repair there is still the clunk  coming 
from the rear- seemingly on rebound, not compression of the shock, though  it 
seems a little better, as I have removed some slop from back there.
I then removed the Bilstein to see of the mounting nuts of shaft where  
loose- they where not. I also articulated the rear control arm and did notice  some 
plat on the rearmost bushing. 
Any ideas out there? 
As a firm believer of doing the easy stuff first (rear upper link), has  
anyone had the same issue that they resolved, I do not want just start replacing  
bushings pel-mel. 
I seem to be pointing my magic wand at the rear diff mount or the rear  
control arm bushing, but do not want to dig in there unless I have to. 
If I have too, it will give me the situation to mount my custom rear sway  
bar which I have been too lazy to do (a lie, I'm in the middle of a 3000+ sq ft  
house renovation I'm doing the GC work on).
Thanks in advance for any guidance.
Cheers,
Jack