duster under dash wiring help

not trying to thread jack here, but im having a similar issue...
Just bought a 74 with a 360. It caught on fire in the same place on the harness. apparently a fuse-able link needs to be there. have a new ballast resistor in there, but something shorted out somewhere else in the dash. apparently the main power coming in through the fire wall goes directly through the amp gauge and then into the rest of the harness... im tryin to figure out how to wire into the main fuse box and bypass that to see if it solves the problem. look into that, maybe you'll find somethin that helps ya out...

I did some research and got an engine harness from this fella named bill evans in PA, evanswiring.com, good quality and price. he doesnt do dash harnesses though. year one does, just a bit more pricey.