How can you tell the exact horizontal and verticle positioning of the F-804H Sideplates? My wing spar spacing is adjusted to exactly 1 7/16" according to plans. There is about a total of 3/16" F-804C flanges not covered by the F-804H sideplate. Is this correct or should both sides be flush? Also, how do you determine the verticle position? If you make the top of F-804H sideplate even with the bottom of the upper longeron (remembering it is upsidedown now) the three temporary tack holes line up right on flutes in the F-804C flanges. F-804H was fabricated according to plans and has been tripple checked. Lastly, what is a temporary tack rivet?