I just replaced the subframe mounts on my 87 SDL yesterday. You have to love California cars although my SDL is originally an Arizona car. The old mounts popped off with simple prying with a screwdriver. They were about 1/2" shorter than the new mounts. I wonder how worn the old ones were.

I set the rear on stands on the rubber bumps. I was able to use the scissors jack from a Toyota to press in the mount. It also seemed that I got better alignment of the mount and receiving hole in the chassis when I lifted the subframe with the scissors jack than with the floor jack. Go figure.

Sixto
91 300SE
87 300SDL
83 300SD