So I just bought my 510 a few days ago. Been driving it a little here and there. I noticed that the speedometer is way off. It has a 280ZX transmission and what I was told was a Subaru rear end. It looks more like a R180 more like it. Are there any tags or I.D. numbers on the trans and diff that can give me an idea of what to look up. I mostly want to know what the gear ratios are. The speedo said I was doing 90 but I was in reality doing 75 and that was in 5th. And the Tach isn't hooked up so I have no idea right now what my RPMs are.