Disc Brake swap-A body Rotors

A couple of the aftermarket disk brake conversion kits come with rotors drilled with both bolt patterns. I believe Wilwood is one, not sure about SSBC. This is an option but you will be stuck getting their parts when you need to do a brake job.

Personally I would use the stuff from the 74 Dart and swap the axles and brakes on the rear. I did this swap three years ago on my 68 Barracuda but swapped in an 8.25 axle that already had the big bolt pattern.