Don't use screws. I only have two machine screws holding mine on. They go into a bracket at the aft spar attach. Here is how I made my gap covers, and I will take some pics of the attach bracket, but it is just a piece of angle that is attached to the waf on the bottom and top, with a blind nut to screw into.
http://krbuilder.org/WingGapCovers/index.html See N64KR at http://KRBuilder.org - Then click on the pics See you at the 2010 - KR Gathering in Richmond, Ky - I39 There is a time for building and a time for FLYING and the time for Flying has begun. Daniel R. Heath - Lexington, SC -----Original Message----- Will small sheet metal screws not pull out ?