I can help you with the wiring, it is pretty simple on the 7MGE.  You can either run from the Toyota Fusebox or integrate into your own.    
	There will be a fuel pump relay (controlled by the AFM on stock 7MGE), main relay (key to on position), and a constant 12V power to ECU so that it can remember it's last fuel trims.  
	If you want to go old school you can just make a switch for everything.  Let me know if you need help with wiring.