You didn't indicate whether you got your numbers from a tag....however, it appears that you've got a W/C Camaro box with a short S10 tailshaft added.
The W/C Camaro boxes run an OD ratio of .63 to .86. First gear ratios from 4.03 to 2.95.
A .86 ratio would have you turning 2601 rpm's at 70 mph with your combo, and 1950 rpm's with the .63 OD. Hopefully, it isn't a .63 OD as that would have you down to 1633 at 60 mph. You'd have a 4 speed with an extremely tall OD. I got caught in that trap!!
Also.....take a peak inside the speedo output hole and see if the speedo drive gear is repositioned on the output shaft so you can run your mechanical speedo.
Either way, I'd do a little back yard detective work...spin the shaft to determine your final drive ratio. Sure would be nice if everything fell into place and it was a straight bolt-up!!!
Hope this helps.
Dave
