I had trouble getting the left block drilled correctly and re-made it a couple of times before finally getting it right. I marked the brackets per the plans for the transverse screws to hold the blocks in place and drilled them on one side to #40. Bolted in the brackets and clamped in the blocks with the canopy clamped in the closed position. Used a drill guide to match drill through the block and other side of bracket. Cleco'd block and drilled second hole. Upsized holes for screws. Dis-assembled, deburred, and countersunk outside of bracket. Reinstalled bracket with bolts and screws. Repeat process for the other side.