What Circuits For Relay?

My 2 cents

Don't ever draw power from the battery, for anything that is normally running with the engine on, on most OEM wired muscle era mopars.

Don't use cheap chinese relays. I've been doing relay kits for 10 years. Had one failure which was related to corrosion from OSPHO being applied nearby. I use only tyco/bosch relays. I'll never use a chinese relay, unless Tyco moves to china, failure rates much higher with those units.

I know the OP is doing a major rewire.