Lean burn removal

I'd leave that as is because of how it splits off into the different main circuits on the driver fender well, (a look at a wiring schematic for these trucks would explain what I mean better) so I'd leave what's there alone as is and run a redundant, 2nd cable (10 ga minimum) from the alternator to the battery but I would put a fuse of some kind into that new line.

I had another /6 powered truck before, and I had to swap engines in that one, as I pulled the old one the engine swung back as it disengaged from the trans, and the valve cover smacked the regulator. Damaged the connector within somehow and I had a "full tilt" charge situation after the replacement engine was in, I ended up having to replace the regulator pigtail to fix.
When testing the charging system on these they say to ground one if the regulator terminals, which in effect bypassed the regulator, and that's how mine acted with the pigtail bring bad. I have noticed a difference in achieved voltage wit different regulators mounted to an otherwise "same everything else" vehicle.