I just noticed recently that the CHG indicator lights up right after starting the engine as it would normally go off after engine starts up. Now when ignition is set to on CHG indicator does not lit and will only light up as soon as the engine starts. I also noticed that the regulator(correct me if use the right term for the small square box near the battery)will become warm even if the truck is parked. Charging is fine when using a tester but i cant seem to figure out if this is an issue with the alternator... i just want to figure out whats causing this issue before considering other options. thanks!

You can test it with a voltmeter, they cost $10- up (or just borrow one)

http://datsun1200.com/modules/mediawi ... ?title=Alternator#Testing