placement of factory GO wing?

Do you have the factory mounts also? Some trunk lids have cut outs from the factory, specifically to mount the hardware, sounds like your trunk lid doesn't.
I think I've posted that info on here before, I'll search my old posts to see.
It would be a lot easier for you to find a lid with the cut out, and if nobody chimes in with dimensions, I'll gladly get you some tomorrow.

All the best,
Giles