1973-1991 Dual fuel tank systems theory of operation

[Hart_Rod]

Originally Posted by Ford Assassin

I guess some of the info here is over this redneck's head. Lol

Dumb it down for me, which color wire do I need to splice into on the firewall relay harness to the LS fuel pump wire into to make it all work? The LS harness already has its own 40 amp relay with power just for the fuel pump. It's a single 12v power wire intended to wire directly to a single fuel pump.

Thanks.

If you don't want to use the factory relay, then something like this coming from your EFI standalone pump relay...