wire size recommedation

130+ amp alternator, 6ga minimum in case it charges hard. The single run is about 7.5 feet, IIRC. You could do 8ga, but, not what I would do if I had the same parts. I think I spoke with you and didn't know the alt was that capacity. Sort of a plan for the worst approach, IMHO.

The smaller wire into the pass compartment likely has nothing to do with the charging system. That likely feeds the fuse block.

The good thing about the EZ wire approach is they are drawing off the alternator for cabin energy. Similar to how chrysler did it.