68 b body discs to 68 dart with factory disc

[tedsweet]

can this be done with a simple rotor change to get big bolt pattern?

 

[hemi71x]

68 "B" body disc brakes are BENDIX.
Totally different from the "A" body Kelsey Hayes disc brakes.
They are totally different animals.
Doesn't work

 

[Professor Fate]

If you just want to keep your KH brakes, but want large bolt circle, follow this thread:
Using mustang rotors for 4.5" bc | For A Bodies Only Mopar Forum
It's a sticky at the top of the brake section.