I decided to route the wing indicator wiring inside the arch and along the outside of the top wishbone. The alternative is through the wheel arch tube itself.
Cable tie clip bonded into the corner of the wing then 2-3 cable ties along the route:
The only point of care is to fix the cable when the wheels are on full lock to make sure there is enough slack to let everything move freely, I ran the cable along the bottom of the top wishbone and in through the wishbone hole in the side panel:
Wiring up is according to the GBS instruction sheet, + I had checked the indicators before fixing them into place:
Black - indicator feed
White - Ground
Ditto on the other side.