Steve, 10Ga wire should be fine.

What did you use for power for the e-fans? Did you use the engine harness (F9-F10 "battery area wires")? If you did, you might check there first, since that's the fuel pump power. Check the fuel pump relay, too. The FSM might have a section on this as well

Just so people know, some e-fans aren't all they're cracked up to be. A fan driven by the motor moves about 2500cfm, from what I remember. That's comparable to a dual FAL setup, which also makes your car shake when they're on. That's also a lot more than less expensive single fans. A Taurus fan does more cfm, but draws a lot of power which adds parasitic loss through the alternator. So, the pros of stock far are tons of cfm, stock shroud is ideal ducting, stock setup is very simple. Anyone ever watch Option videos? EVERYONE has a stock fan/shroud.