[joyridin']

I probably missed the part about already having rims. The old CMC had a pretty narrow wheel well and you could put about an 8" wide tire, since the molds were the same, I assume the Streetbeast is the same. They were designed for a Mustang 2 rear axle width to give the rims some offset. If you go wider, it might look a bit odd.

I had the same set-up as you. I chopped off the upper spring mounts and made my own mounts while using coilovers. I then had the 1994 axle narrowed 2.5" on each side and put new shorter axles. I could then put an 11" rear tire under the car.