I wouldn't put the U-Channel.
I prefer without.
If you had the time (many hours ) you could have filed the edge of the window cut for a perfect straight edge, but it takes time and patience with a file.
I asked Dwood to cut my side panel, I wanted a perfect cut and I didn't want to file for HOURS. Laser cutting machine
I gave wrong measurements to Dwood for the intake holes and I had to file them for 2 hours to reach perfection. Dremel and Jigsaw are great, but for rough cuts, the file is the key
That was my
I agree for laser straight cuts it would look Awesome.. But for me i have to edge it with Molding.. I WILL make it look GOOD!! ~~