Why was the 10A fuse put in before the positive buss? Was it part of the aftermarket wiring or you added it? It was originally for the fan relay wiring harness. When we put the fuse block in we cut it and used it from battery to the fuse block. Just curious. Why so many grounds?
If the battery is in the trunk, you should have a negative cable that runs from the battery terminal to a spot on the frame cleared of paint and undercoating, then forward to the engine itself, with additional ground wires from the firewall to the engine, and from the radiator support to the engine. I put my busses in the engine bay so there's les wires the length of the car and everything gets grounded easily.
The pertronix in the distributor is fried. A good friend once said electrical is all about keeping the smoke in. Once you let the smoke out, it's dead.