You are incorrect..... Almost everyone uses a Poly Carbonate (Lexan) and attaches the side panels directly to the nerf bars and it is UAS legal.
Bob,
Paragraph E under bodywork and dimensions clearly says "lexan may be used in wedge design in conjunction with standard kart side panel or other acceptable side panel material as long as the lexan is attached at least 4 inches above the bottom of the standard kart side panel." That's direct quote from the rule book. So anything different should seriously be looked at in tech. As lexan attached directly to the nerf bars is clearly not legal. But then there's always local option I suppose. Those performing tech should really read the rules, all of them, more carefully. Especially when it comes time for new rules and the process of changing them.