[TR] TR6 Still has an Issue

[TR250Driver at aol.com]

Hey Guys,
I spent some shop time on the Six.  The mystery miss is gone once I  
changed the plugs to Champions, reset the point gap and advanced the timing  a 
bit.  The miss may come back once the new plugs are burnt in, I  don't know. 
The woodpecker metal like tapping came out of the right rear  suspension once 
I greased the urethane trailing arm bushings, renewed the spring  rubber 
packings and replaced the shock links.
 
Now I have the last issue to deal with.  Every now and then the right  rear 
will make a very bad noise when taking up the drive in reverse or around  
corners.  This is more than a clunk.  It is like a gear slipping with  the 
resulting lurch. I suspect a bad bearing but who's to know?  Any  comments? 
 
Decision time is now.  The Featured Marque Six to Jekyll Island  or the 
GT6.  The GT6 has no issues as of now.  I am  trailering so not to worry but 
the GT6 was the only Triumph to leave me on  the side of the road lately when 
it snapped a u-joint in half.  I don't  like to work on cars at a National 
Convention. Although it is a great  time to do that since all the experts are 
there and anyone with a bonnet up and  tools out draws a big crowd. 
 
The Six is a pig at autocross with the redlines the GT6 may have potential. 
 Whatever, I would like to resolve this crunching noise in the TR6 rear.   
Any thoughts on that would be appreciated.
Thanks,
Darrell