Re: do I need the spindles for this swap?
The inner wheel bearing is different for the discs, so the answer is yes, change the spindles. If you go with the 77-78 6 bolt caliper style they will bolt on, but you may need to grind the knuckle and caliper a bit for clearance. If you choose the newer 2 bolt style you'll need to swap knuckles as well. Good luck.
76 CJ5,2.5" lift/Rancho 9000's,258/T-177/D300,HEI,Offy,Locked F&R