True, except 1963 & 1965 models (A,B,C) have rugged "bus bar" feed-thrus in the bulkhead for ammeter current.
I second the bypass idea of running a thick wire (~8 awg) from the ALT big stud to BATT+. If you want to keep your dash ammeter functional, you can add a diode pair in series so at low currents it mostly flows thru the ammeter. I posted instructions, but don't try it unless technically competent.