Lawdawg, I don't know what size plane you are flying, but if it is 40 size or larger, use at least #10 screws, and 1/4 would be better. I mounted a landing gear a 40 sized plane with four #8 screws and I would pop the heads off every other landing.

Something to keep in mind with the nulong bolts, you don't want to tighten them real tight. Bring them up with your fingers then use your wrench or screwdrive and give them a half turn more. The stretch and if you really tighten them down, they will be near the breaking point and the first hard landing they come apart. If you are trapped into a #6 or #8 screw use brass stove bolts or steel with a 1/4 cut with a hack saw at the head.

Last, I get all my nylon bolts at the local hardware store. They have a selection from #6 up to 5/16 or so.

Don