Given that the top skin measures 25mm longer than the lower (to center of leading edge) it seemed reasonable there would be extra material to remove beyond the 18mm top flange as noted in the Assembly Guide. Measuring from the rear spar flange at the outer-most center ribs revealed an extra 4mm on the left and 8mm on the right. Re-measured the spar-to-spar distances and found this same 4mm difference between the front spar web and trailing top flange at each end. This difference was not present on the bottom flanges and I could not determine how this deviation crept into my assembly. This difference will cause a 0.1 degree out-of-square angle from one side to the other. Assuming this will not cause aesthetic, mechanical or functional issues I drew a straight line connecting the 4mm and 8mm excess skin marks and trimmed off with snips then smoothed with files. Assembly of the tips and elevator will provide the final verifications of acceptability and whether I was correct to ASS-U-ME :-)
