I have the rear SCE adapters direct from Supercar Engineering for the Evo shocks and springs and there is an issue with them that has been noted by others.
The 3/S has a R lower shock mount with a larger diameter taper than the GVR4. This means that if you install the tapers of the mount and adapter aligned with each other the way they were designed for, the fit will be sloppy. If the adapter is installed with tapers opposite to each other, the smaller diameter of the taper on the adapter fits closely (no slop) on the larger end of the mount closest to the trailing arm.
I can see how this would work short term, but there will be a very small amount of bearing surface between the tapered mounting stud and the reverse tapered adapter. I am afraid to run it this way as I think the white adapter bushing (feels like nylon) is going to deform and get hogged out and loose.