Lets start with the Front Shock top mount buffers:
The Clauss buffers I have are for a Pseries shock; and include 2 polyurethane buffers, large washer, lock washwer, nyloc nut. Compared to the stock SF rubber buffers, the inside diameter of both are the same, but the Clauss buffers have a larger outside diameter. The bottom buffer can be used as is, since it rests against a flat steel plate. The top buffer OD will need to be turned down to fit inside the metal cup. This should be easy, its just polyurethane.
My only concern is that the stock rubber buffers compress and swell when the washer/nut is tightened, creating a snug fit around the top of the shock shaft. The Clauss buffers are much harder, and I dont see them compressing or swelling. So perhaps they will allow the shock shaft to 'float' inside, and contact the fork. We'll see once installed..
Clauss Mounts compared to stock rubber mounts
ID is the same, OD is larger on the Clauss Pseries buffers
rubber ID has about 1mm play all around between the shock shaft
Same ID play on the Clauss version, but with larger OD. No problem for the bottom buffer. might be a slight improvement and more stable than the smaller rubber, in addition to it being firm Poly.
Stock rubber Top buffer, fits in the metal cup snuggly.
Clauss buffer is too big for the cup. Will turn down the OD to fit. easy peezy