how would i know if its internally or external regulated?

Okay, I looked up the information on the alternator / regulator for your truck, good news I found my question. I refered to my ( Chiltons Toyota Trucks 1970 - 1988 manual ) & on page ( 3 - 12 engine & engine overhaul ) subsection ( alternators ) The 1970 - 1979 models utilize a seperate, adjustable regulator : meanwhile the 1980 - 1988 models utilize a transitorized non-adjustable regulator, integral with the alternator itself which is easily converted to a h.o. alternator, because most h.o. alternators have this integral regulator on it, meanwhile yours is located probably on the fender or firewall, Im not 100 % on the position, nor does the manual explain this. More info and thought therefore is needed, lemme do some more research before I speak without thinking

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