Battery becoming very hot

Why?
Mattax- might have to rewire both cables.
Karl and I built the engine, and I know he is awesome on wiring.

Do you think it would be beneficial to change the harness? Thank you
Which one and why?

If the answer to my questions in post #64 are no, have Karl help you.
Even if they are yes, it will go 10 times quicker.
We need positive answers about where each feed connects.

If you want to spend money, use it for buying or renting open barrel crimpers, factory style terminals for various wire sizes and things like that. And a battery charger that can do a slow charge ( 2 amps and under) if you don't have already.