A day later than I had planned, I got down to the HARM. What I found is that the ride pad structure is indeed installed at 90 degrees to the actual bottom of the sponsons. With that said, I found something else that I hadn't taken into account. I rechecked the angle of the inner edge bevel and made a shocking discovery. I had assumed that the bevel was at 45 degrees for it's whole length. What I found today is that it's actually at 50 degrees at the sponson transom and 54 degrees at the forward most internal frame location of the model's sponson. That pretty much tells me why I couldn't get anything to line up properly when I was trying to redraw the sponson frames. At least, at this point, I don't have to start from scratch