Starting to wire my car. I have a Painless full chassis harness to integrate with a GM ECM/engine harness, along with Vintage Air wiring. I am finding some redundancies and wondering if there are any implications. The first one is powering the fuel pump. I know I need a switched power source. Both Painless and the GM harness have provisions for this. I am leaning towards using the Painless one because it routs both a power and fuel sending lead with the rear tail lights - making it convenient to the in-tank pump. I can't see any reason not to use this one. Any thoughts on this? Also, if anyone has installed both of these systems, I would be interested in any other quirks that may await me... thanks.