Bumper Question

[RunAdamRun]

Our team 5145, a rookie team, has a bumper question. We received the AM14U drive-train kit and we are unsure if it is okay for our bumpers to come over the sides of our drive-train because they need to be 5 inches tall and our drive train is only 3 3/4 inches. So can the wood of the bumpers be wider than the frame's height. Also, the AM14U has a gap between the center frame and the outer frame that holds the wheels together. Is it okay that we do not have the wheel gap covered when the frame goes on because in the rules it says in R26 B. "the gap between the backing material and the frame must not be greater than 1/4in." So does the wheel gap not count as being backed? Any other tips on bumpers would also be appreciated.