C-body rotors only fit C body spindles. Same with the caliper adaptors. The C body rotor is thicker too, so the calipers won't work on anything else either. And for the next question, C body spindles pretty much only fit C bodies. I do know of ONE guy that runs C body spindles on his Challenger, with C rotors, Viper calipers, A body LCA's, racing ball joints, etc etc. But he pretty much re-engineered his entire front suspension. You probably don't want to do that. Here's the info if you want to though....
http://www.cuda-challenger.com/cc/index.php?topic=73985.0
The 11 3/4" rotors you need are off of B or R bodies. They bolt right on with the proper caliper brackets, don't even have to change the calipers if you get the right caliper brackets. Here are the bearings, inner and outer are the same for the 11 " and 11 3/4". The problem seems the B250 rotor setup uses a 1.24" thick disk, the 1977 uses a 1" thick disk. It will take a little shimming.
CHRYSLER CORDOBA (1976 - 1979)
CHRYSLER NEW YORKER (1979 - 1981)
CHRYSLER NEWPORT (1979 - 1981)
DODGE CHARGER (1976 - 1978 )
DODGE CORONET (1975 - 1976)
DODGE MAGNUM 1979
DODGE MONACO (1977 - 1978 )
DODGE ST. REGIS (1979 - 1981)
PLYMOUTH FURY (1976 - 1978 )
PLYMOUTH FURY SALON (1977 - 1978 )
PLYMOUTH FURY SPORT (1977 - 1978 )
PLYMOUTH FURY SPORT SUBURBAN (1977 - 1978 )
PLYMOUTH FURY SUBURBAN (1977 - 1978 )
PLYMOUTH GRAN FURY (1980 - 1981)
PLYMOUTH GRAN FURY SALON 1980