Frame Flaps
I thought about plugging the holes but, being odd sizes could not find suitable plugs. Then it dawned - why not make some 'frame flaps' that would cover the holes. I am experimenting with using some heavy, clear vinyl from old vinyl strip door sections, cut and fitted to each box member. If you look at the leading edges of the rear suspension arms, they both have a black plastic/vinyl cover held in place with standard push pins. I plan on using a similar method with the frame flaps.
I understand about the sand and small pebbles getting up into the frame, because in sunny sandy Florida it is always the norm.
I looked at the holes in the semi-boxed frame and had an idea. I have been buying various items for my Jet Engine shop lately and saw that they have different types and sizes of Teflon plugs at Ace Hardware.
I looked to see how they were designed. They are hollow with small holes in the diameter. Up inside the taper the "feet" of the plug will keep out foreign debris because the hole tappers.
I think that this is just a smaller version of what your idea is for the flaps. The other benefit is that with a "non" unplugged hole, no water will be trapped and no rust will be able to form.
bozzzz: I checked our Ace hardware for suitable plugs and could not find the automotive style blanking plugs I wanted. I bought an assortment of plastic hole plugs, round table caps, metal caps, etc, but nothing would fit right.





