Don't worry, its about the same size as an S14. From what I've seen it even sits in roughly the same location, only leans to the other side. I'm gathering my info on putting one of the SR's I have into my E30 in the spring. Now that I work with 3D modeling and CNC machines designing some mounts and cutting them will be pretty easy. There's a couple of guys on E30tech and bimmerforums who have them in E30's and I beleive I found an E28 with one as well.