Would the cutout relay ever close?

 

So it's really a simple DC circuit. Either way the battery is hooked up provides a complete path. Do the electrons move backwards or forwards through the wires?

No, they move from negative to positive to charge the battery. Does the generator care what that path is?

No, it's still a complete circuit no matter what the path is. Does the ammeter care.

Very much so. It has to "feel" the current moving in the correct direction.

Does the regulator see an overcharge difference in potential? Yes, so it'll operate normally.

When my truck was connected negative ground, the generator was still charging the battery. The ammeter didn't like it, but the battery was charging.

That's my $0.02 worth.

 

shopping for a '48 F-1 239 flathead v8 wiring harness..it runs around $300. Does that sound like the right price?
Also truck was originally a flat head 6..will v8 harness make any difference for example wiring lengths, wiring layout,etc?

 

Yes. It will make a huge difference, and an unnecessary amount of work if you buy a flat 6 harness when you have a flat 8, or vice versa. All kinds of things are different. I bought mine from an ebay vendor, but it was the Dennis Carpenter harness when I got it. I'm very satisfied with it. Yes, I paid about $150-$200 more probably when it was all said and done, as compared to buying one of those universal (EZ Wire, Rebel, etc.) kits. But it's all cut to fit, color coded, with the correct ends, etc. It was simple mindless work. That was worth the extra money just so that I didn't have to "think" about it, cut, crimp, chase wires, etc. Plus it looks identical to stock.

 

The wiring routing is different between the v8 and 6 cyl. Does your truck have the battery still in the six cylinder position, not going back and read the entire thread? If so, neither wiring is going to fit correctly without modifications. Is there any chance you'll want to convert to 12V? If so, a different route to take. Can't help on price.
Edit: Looks like Doc covered the subject quite well while I was

 

yes battery in 6 cyl position..converting to 12v maybe above my paygrade

 

Perhaps moving the battery to the correct V8 location, detail pictures of someone's correct V8 wiring and a new correct V8 wiring harness would be your best bet.