Which rubber mounts? There are 2 sets of subframe-to-body mounts, which are different sizes; three rubber differential-to-subframe mounts, and then 5 suspension links with rubber bushings on each end.
Some photos of my subframe mount job (near bottom) :
http://www.w124performance.com/images/W124_subframe/
A nice tutorial on the forward subframe mount job (6MB PDF file) :
http://www.w124performance.com/docs/mb/W124/subframe_bushing_install.pdf
If replacing the rear pair, I'd install the Sportline mounts...
