I pulled off the old painter tape on the roll bar. it had several Sharpie lines from prior fittings and it clouded the picture for the final trim line. New tape. New 3/8 inch measurement from forward face of the roll bar. Nice thin crisp line to denote the rear edge of the main canopy. Reinstalled canopy and with it locked down, I laid electrical tape on the top, whose aft edge matched the line I drew and could see through the canopy. A couple things come to mind. The previous cut line was different and that was due to the fact the canopy was not drilled or clecoed when I marked it for the big cut. I also left a little surplus. The final cut was not a parallel cut. It went from thin to 3/16 wide. Don't even think about final cuts until you have the canopy drilled and clecoed down. Even then, as I mentioned previously, a hot day will expand the canopy somewhere around a 1/16 or more. I plan to leave 3/32 to 1/8 gap between canopy and rear window. Spent an hour finishing the final rear edge (scraping, filing, sanding, more scraping). Pictures later.