Before I drill the wing aft spar attachment holes, I thought it would be a good idea to install the flaps and see how they tuck under the fuselage and any clearance issues with the side of the fuselage. First thing I noticed was the flaps could not be raised to the up position because the flap edge would rub against the side of the fuselage. I decided to scribe a line on the top of the flap with my compass set at 1/8" to follow the contour of the fuselage. I removed the flaps and trimmed the excess material with my metal shears and clean the edges with my die grinder using a small 1" 3M deburring wheel. I installed the flaps and checked the fit. The left flap gap was perfect, but I had to remove the right flap and trim some more. With the flaps done, I removed them and stored away. Yesterday, I had picked up a couple of pieces of steel from Reliable Hardware to use as drill guide blocks. I placed the blocks against the aft spar and found that a little trimming was on order. I marked the blocks and used my Makita abrasive saw to trim each block to fit. Tomorrow I will drill the blocks to #30 drill size.
