Fuse instead of fusable link blows while driving.

[TCLARK]

The fuse of my Frankenstien started blowing while driving and truck. I put in another 30 fuse and starts right up. I'ts an I6 converted to V8 with HEI. Been my daily driver for years like this. Just started blowing fuses. Put new Voltage Regulator on, same thing. Had Alternator checked, OK. Getting ready to put '67 body on this '72 frame with new wiring harness in the near future. Do want to put new harness on the old body right now. This wiring is scary, but it's been working for years like this.Any help appreciated !