Cerwin, what gears are currently in your 8.25" rear? If memory serves me correctly, the 2.45:1 gears in an 8.25" rear can't be exchanged for a higher gear set due to the design of the gears and housing. If you have anything higher that a 2.45 then I believe you can exchange gears as you like. I'll let some of the guys that have more experience than me with these 8.25" rear ends confirm or deny that theory, but check your gears in the 8.25" and confirm exactly what is in there now. :)