BBP rotors for a 1968 Dart GT using the same 4-piston calipers???

dano said
If I had this to do all over again, I would get some 73-up Disc brake spindles, a 66-67 B-Body rear or Custom Dana 60 with BBP axles and order Dr Diff 13" Cobra Front brake kit and 11.5" rear, then get 17x8 rims from a 1994-2004 Mustang application (don't have to be from a mustang) and enjoy the tons of far superior tire designs and compounds over 14" and 15" offerings and more brake pad options. Toss on some QA1 upper A's, adjustable strut rods, better shocks Bilstein, Fox, Hotchkis, Viking etc) , large sway bars and larger torsion bars to fit your engine weight and enjoy a good handling and stopping car.

And how many thousands of dollars is all that stuff you just listed?
All he wanted to know is if he could use a large bolt pattern disk with the KH caliper and spindle.

Yes this can be done, with an early mustang rotor. Outer diameter needs to be cut down slightly, and the recess in the back of the rotor for the inner bearing race needs to be machined a little deeper (around 1/4") to move the bearing farther into the hub, moving the disk farther in on the spindle. This will center the disk in the fixed caliper.

Follow the link posted by joeboy above and you can read all about it. This is the setup I have on my car.