If you want to know what you are going into. Here are my 2 threads on replacing the suspension bushings with the SPL catalog.
The Complete SPL Front Suspension
The Complete SPL Rear Suspension (Almost)
As for replacing the rear sub-frame bushings. Believe you only have 2 choices. The solid SPL kit which replaces the bushing all together. And the Z1 kit which you install parts into the stock bushing. The Z1 kit is the one you want. It still has some flex in it unlike the SPL bushings.