SHOULD is the key word - I had bought a pre-welded 2.5RS center differential and it was eledged to fit (the part numbers even matched my Legacy Center Diff), but it did not. Since then, I'm not trusting fitments until I can put the part in and drive away with it. I'd imagine that the 2.5RS parts would fit, or at least hope that they would, since the RS canme with a rear VLSD, which would be pretty good for what I'm trying to do. The diff housing looks kinda like a steer skull or something, it's probably 2 feet long and only houses a 6.25" ring gear

I want to make sure that I have something that I can really beat on, but I'm worried that my new infinite-way diff may destroy my axles, so I'm in the market for a Ford 9" or Toyota Truck rear end. Yes, converting to solid axle is, IMO, a bit ahead of a welded rear end on the hardcore scale, and I will definitely be retaining the WRX coilovers