Use one bolt. Why does it have to be nylon? What's wrong with steel? Or aluminum? If you're going to hit somthing with the wing hard enough to break the nylon bolt the rest is history anyway. Same holds true if the nylon bolt breaks in flight. Say good night, right?

To make yourself feel better, and to act as a safety, you an drill a 1/16" hole through one of the locator pins at the inside edge of the fuselage. Inset a "hairpin cotter" through the hole and that will help give you that "locked in" feeling.