Help Identify 8 1/4 differential?

Well, it looks like badsport dialed it in. I believe this has the correct spring perch dimensions for my car but the overall width is about 1.75" narrower. I am questioning whether I should put it in the car now but at least I have a model to look for to buy parts if I decide to try it. Thanks everyone for your input, I really appreciate the help. May have to sell this one and look for an
8 3/4 as that seems to be the one of choice anyway. This one is supposed to be a 3:21 to 1 ratio which would be perfect for my build.
DR