I would do the change and see if you can have your driveshaft shoten locally I'm almost sure that the 8 3/4 pinion yoke sticks out further, its longer, than the 8 1/4 does Let us know what you do BTW, you may have a 7 1/4 instead of the 8 1/4
Last edited by Cab_Burge; 06/23/1502:44 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
I'm almost sure that the 8 3/4 pinion yoke sticks out further, its longer, than the 8 1/4 does 
Let us know what you do 
BTW, you may have a 7 1/4 instead of the 8 1/4 