Usually V/reg is on or off. It sounds as if the gen is just putting out @ low voltage. Do you have a local Starter Generator shop? Sometimes they can just throw a set of brushes in em and they're good for another 10 years.
1960 Convertible (Orig owner)
Pic of car with my son Justin (15 Y/O 6'1")
Poss 3rd Gen T/B owner