Panel to wingtip wire run estimate?

Hi all.

I don't have my fuselage kit yet, but I'm about to run wires in the wings (wing tip lights, AP and trim motors, etc.). I'm aware of the wire gauge chart from AC 43.13, which takes the length as one of the parameters - so I'm wondering what would be an approximate length from the wingtip to the center of the panel - can anyone tell me what length they used?

Also, when using that chart, since I'm not grounding locally at the wingtip but rather bringing back a ground wire, should I double the length for calculating the gauge?

Thanks!
Rodrigo

IIRC, I initially ran about 25', but trimmed it back to something closer to 20' based upon the exact routing and termination points.

Yes, calculate the gauge based upon the whole run from the bus to the device and back to the grounding point