I took the long way home on the '89 D100 318 to go 1 wire conversion and eliminate the computer controlled voltage regulator.
Original 2 pulley Alternator.
View attachment 1716307793
Swapped in a 1985 Ford double pulley Alternator with an aftermarket 1 wire conversion. Charge wire goes direct to the battery with an inline fuse.
View attachment 1716307798
ATP F7078 Ford 1 Wire Alternator Conversion
Kit by Transpo
American Made
Advance Truck Parts
Sunrise, FL
View attachment 1716307800
View attachment 1716307801
View attachment 1716307802
Wired in simple parts store voltage gauge to a random 12 volt feed, simple and works good to follow voltage output.
View attachment 1716307806
Tried other external regulators but no joy. This setup works well for me.
☆☆☆☆☆