I just changed all 4 gaskets on the rear of my 84. I went a little too far though account I had to replace the rear tire at the same time. What I did was take off the rear frame portion. Quite easy really and you dont have to be a contorsionist (sp) to get your wrenches in to loosen off the rear manifolds. I used this time to clean up all the road grime from the last 25 years. I found that I had to loosen the nuts on the front exhaust also to allow a little free play to get all the gaskets in. I also took the ring clamps over to the bench and shaved a little off the stop to allow for more clamping force. No more leaks, I can hardly hear it run now. Of course while the bike was down i also cleaned the carbs, eliminated the yics and changed all the fluids, installed new battery. Now if it ever stops snowing I can ride. Gotta love Alberta in the spring time!
Darrell