65 barracuda not charging PLZ help

It can.
A later revised squareback alternator has a much higher field current draw than the alternators these cars came with.
Seen something like 7 amps in a 1980s shop manual, vs somehting like 2.5 amps in most of our A-bodies.

That's voltage.
Current we'ld have to calculate based on how much votlage was lost going through the resistor.
forgot to mention my alternator is a 60amp