RE: MPlex TwinStar Recommendation
Congratulations!! You have acquired one of the best-flying foamies around. The "gap" as you call it SHOULD be at the trailing edge, and is there to allow the cooling air current to exit the plane. So the wing mounts flush up to the cockpit cover. Anyway, the hole you're going to drill into the plywood plate will align with the hole in the front of the wing, so I really don't know how you're gonna go wrong.
Good luck, and happy flying!!