I have a 92 firebird v6 rear end 7.5 in. / 10 bolt. wanting to get a spool and need to know if this is 26, 27 or 28 spline axles. I have been told '90 - '92 are 28 spline, but cannot find any ID numbers on the axle tubes or diff. cover. Please help ASAP as I would like to get the parts ordered today! Thanks!!

 

92 would have 28 spline axles, assuming the axle assembly is original to the car.

However, a spool is only suitable for dedicated race cars. On asphalt if you have to take any turns, you're going to wear the hell out of your tires, and you'll probably break an axle.