66 Valiant - stranded on road trip

Update: Upgraded Fusible link replacement to 30A fuse and 10 gauge wire. Car runs fine with this in, but after 5 minutes, fuse blows and the car runs rough, fuse was hot. I'm guessing now i have a short? But i'm confused, would a short blow the fuse right away?

I've bypassed the ammeter with nothing replacing it? Would this cause the over powering?