For EFI system, I would suggest going directly from the battery. Not piggy backing on some other circuit that may have "dirty" power, or interference and noise from other electrical components.
I'd run your full time power straight from the battery. And the wire you need with power while running, come off the battery and add a relay. Then you can use power from some thing like the carb anti-diesel solenoid or the windshield wiper motor to trigger the relay.
I have looked into the aces efi systems, but not installed them. For components, their big ones are coming from china. The identical intake manifolds and fuel rail kits you can order from overseas. But aces will sell you their intake kits if you want to buy those from a US supplier and then run a different computer. I ended up going with the other guys instead, mostly doe to the features of the computer. Aces doesn't do transmission control. And aces has less wires for inputs and outputs, with some of them preset for things I dont need like 2-step limiters and nitrous systems. Its been a minute since I checked on them, but I wanna say they did not use the 2 wires for the AC system. 1 as an input to know when the AC system was active to bump the idle. The other 1 as an output for WOT so you could disable the AC compressor.
