Need Help With Driveshaft Issue
It only costs about $50 to have a drive shaft shortened and balanced. I have done it twice now; first when I replaced the 3 spd manual with a long tail shaft A833OD and second when I swapped the 7.25 for a 8.25.
You can get a conversion u-joint at NAPA that will fit the smaller yoke on the drive shaft and larger one on the 8.75 or get the small u-joint yoke for the 8.75 or when you have the shaft shortened have them put the bigger yoke on the shaft.