the mount on my '88 FC L33 CAI T56 T2 rear end sheared a while ago. I read Bikedad's thread on dropping the rear subframe and welding up 2 bars to reinforce it, but still leave a little movement capability, but it looked like a lot of work, so here is my solution>
First off I have to preface this by saying if I read someone did this I'd probably think they were crazy and "it's not the right way to do it" but it works really well and costs very little.
There is not a lot of room between the top of the diff nose and the bottom of the chassis, not sure if the coupes are different than the verts, but anyway, the rubber mount on the side was clearly sheared, when readjsuted and retightened the mount bolts weren't holding and the diff was flopping up and down and hitting the underside rubber snubber which is about 1/2" above the diff nose.
I had a big hunk of truck tire scavenged off the side of the highway saved for just this application. I cut a big chunk of it out, (maybe about 3X6) cut and ground a low spot to fit around the chassis pinion snubber and under the cross brace on the underside of the chassis, used a bar to push the diff nose down a little, fitted it into place and secured it with a big hose clamp.
No more problems and I didn't notice any extra chassis noise, launches are a lot smoother with no wheels hop, Yeah
I'll probably get a lot of crap about it on the forum and if someone looked at the big hose clamp around the diff nose, they'd probably think WTF, but it works great, I could have screwed the pad to the underside of the chassis, but the hose clamp was a lot faster, saved $100 and it will never shear
