OK battery went dead couple days ago. on my 81 FJ40. Thought it was battery, but after putting in on charger it tested good...held 12.6 volts. So decided to test alternator using battery cables with a multi-meter. No change in battery voltage after starting. So got to be alternator right? So I ordered a replacement. I removed the old one and as an afterthought I decided to have it bench tested at auto parts store. It tested good. So now I'm wondering what is going on. Need some help from some experts (Coolerman??) Do I change alternator, battery, etc.? Is there a fuze or connection I'm not aware of. BTW, the alternator is original to the truck and has never been changed..gotta love quality parts. Thanks in advance.