After finishing the metal part of the vertical stab, I thought that I had messed up. Even though I did not rivet the top row of holes where the fiberglass tip would go, I thought it was just too tight for the tip to fit. The SONEXTALK discussion group provided some good thoughts. I had considered placing the tip on TOP of the upper rib (is supposed to sandwich between the rib and the skin)., or obtaining a new top rib and riveting it upside-down to the existing rib, then mounting the tip to that. However, one other builder said to just try and force the rib in. I started from the rear of the top rib, back by the main spar, and this allowed it to fit just fine. Messed with it quite awhile to try and "adjust-out" some asymmetry at the tail of the tip. A friend at work (fellow EAA'er) suggested taking a heat gun to it. Will have to try. For now, the tip is off.