wiring

The light harness for the same series would help a lot and usually those wires are still good since out of the heat zone. But, if adding relays for the lights, as many do, you will be hacking that too. The engine wire is fairly simple if a 1960's car. Junkyard wires are usually useless since friable insulation. If retrofitting HEI that needs to be customized anyway. If using the bulkhead connector, most critical is to get the engine-side plastic holders from a junkyard car (or new harness from Year One or M&H). Some install a custom bulkhead or just straight-wire thru as most/all modern cars do.