I'm up to lay out for the rivit line for the elevator hinge. The 40 pitch works out between the ribs. But outside the last rib to the end rib I ended up with 34 pitch to evenly space the last two rivits to the end of the hinge. Then 37 to get even spacing for the 5 from the end of the hinge to end rib. If anyone knows if this is something that will come back to bite me please speak up. I know the 37 is with tolerance set in the construction guide. I'm wondering about the 34. Stopped there for the weekend. I have not drilled anything yet, so it's unchangeable at this piont.