I have a 67 rs with the 12 bolt rear and recently installed the 4 wheel disc conversion and the rear wheel studs are to short with the new rotors on and was wondering if anybody has done this conversion or if anyone has replaced there studs with longer ones?

 

 

Visit a NAPA store, or a store selling Dorman products - those orange drawers behind the counter as Dorman markets longer than stock studs.
Take one along for comparison and measure what you need for length.

 

Dorman #610-157, 2-1/8" long. Your current ones are 1-1/2" long.