Short under the dash.

Ammeter is bypassed as well as having the main power to/from the interior bypassing the bulkhead connector. Tbh, I don’t know if I even have a fusible link. I may have accidentally cut it out when I did the bulkhead bypass

You need a fuse of some sort or you will be sorry when all the wires melt together,
maybe already happened! I would start pealing the rap off in places and look.