Drew center lines and register marks on the Gretz pitot mounting plate and clamped it to the spar flange. Centered the plate flange over the four holes closest to the first rib inboard of the left bellcrank and drilled the four holes to #40. Removed the plate from the spar and removed all the marks. Used a piece of scrap 0.025x1/2" angle to locate the outboard rivet line on the mounting plate and mirrored the line on the inboard side. Drilled twelve equally spaced #40 holes around the perimeter of the plate.
