Q&A

Probably --- nowhere.

But before you think about running wiring, think about what else is inline between the fuel pump and vref (power) - such as possibly a faulty relay.

This is where a legitimate factory wiring diagram is indispensable. You can ohm out (check wires for excessive resistance, indicating an open circuit...) sections of wire at a time, and then find out where the power stops.

Lastly, if you do end up replacing wiring, you probably only need to "overlay" the wiring in question. This would mean taking some bulk wire of proper size and gauge and just replacing a section that you have identified as faulty.

I don't think you'd find a whole loom for this car any more, and if you did, you wouldn't want to spend the big money on it.

I wish you luck in your repair process.
-Dave