On to trimming the cowl at the front. The cowl is epoxy fiberglass two piece, top and bottom.
This involves a bit of magic and careful trimming. The idea is to match the two halves of the cowl at the front, removing material from both, such that an imaginary line at the midpoint of the 13" circle matches to the join line of the right and left top and bottom cowl air inlet sides.
Placed a 36" metal ruler across the midpoint of the 13" circle to provide a reference line to determine how much material to remove from the top and bottom cowl. Making this more interesting, the interior air inlet has a tab where two cowl halves overlap, which needs to be preserved so that a fastener can be installed.
Starting by removing a 1/4" from the top and bottom, and determined the sides needed perhaps another 1/8". Difficult to tell because the sides are overlapping at this point and there is interference at the front, of the sides, which must be trimmed carefully.
Determine another 1/4" inch needed removal (1/8" top and bottom), and then another. With this I could not remove from the bottom to preserve the tab for the interior air inlet. Some more minor adjustments and finally the forward cowl fits together with the same distance around the 13" template. A LOT more work is needed...
