Charging Issues,

Asked regularly. Many simple tests you can run (search). It is a very simple circuit. 12 V on the single field terminal will command "full output". Find which component isn't doing its job, using a multimeter and jumper wires, and could be as simple as a bad ground (very common - from ALT case to BATT- or from Vreg case to BATT-). The bulkhead connector often gets melted, but less likely on a 1963 since yours has dedicated lugs to feed the big ALT and BATT wires thru.