Save your ZAP CA caps. When you drill some holes in a wing for wing bolts, insert and glue the Zap CA cap into the hole with the open end facing outward. They're just the right size to accomodate the size of the bolt head. Sand it flush with the top of the wing. Then drill and tap as normal. Voila! Now you have a very durable (screwdriver "ding" proof) liner for the bolt hole. The part of the cap that you drill will also accept the same (1/4 -20) tap, so when you remove the wings, the bolts will have enough "bite" to remain with the wing.