Mine is the same, but as you scribe/cut to better match the fender it moves the aluminum in to get more coverage on the fiberglass below, also I pushed the aluminum back so I had about 1/2"-3/4" of the fiberglass showing on the bottom in front of the aluminum, this front and rear of the rear wheel openings. This gave me plenty of room for 3 rivets for attachment.
I centered my top tab on the frame, I think a little lower than what your showing.