I hate to state the obvious but make sure you don't have the battery terminals reversed. after that unplug the voltage regulator and make sure everything else is fine. then plug the v reg in again. Voltage regulator on the luv is mechanical with relays so something might be stuck in the wrong position. Wack the cover of the v reg a couple of times with the handle of a screw driver. I made one work by doing that once.
Only other thing might be you wired something wrong on your alternator. were you doing anything with it lately?
any other hot voltage wires pinched to gorund might also be the problem
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Did a v8 conversion in 1981 on my '76 luv
Current Fleet
#1 1980 Black 2wd, #2 1980 Blue 2wd, #3 1980 Black 4x4 #4 1980 black 2wd Long bed #5 1979 black 4x4 #6 1977 red 2WD
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