Actually in the early 70s I believe neither the C or D had ILS, only TACAN & ADF, ADF of course used primarily for music.
In fact IIRC the Fs at TUS were upgraded with ILS first....you could do an ILS on your instrument check before going back to your TACAN/ADF only single-seater. Ds ILS came later, not sure about the Cs, although Niagara & Des Moines had Cs for a long time.
The only thing I remember in the C/D/F was a yaw damper, don't recall an auto-pilot, but it's been a looonnnggg time ago.
edit: BTW they put the ILS in the Guard C(?), D & Fs because most of the ANG units were at civvy airfields with ILS.