Nathan,
It looks like you are getting close. Don't expect the lexan to stay formed. Just bend it cold. Once you get the windshield cut to where it fits against the bow just screw it place. It might help to tilt the bow so it leans forward a bit. Be sure to drill the holes in the lexan a little larger than the screws and use some washers. Mine are #6 sheet metal screws. On the bottom where the windshield touches the fuselage just make some aluminum tabs. I think the plans show the tabs. Keep plugging away. You're getting close.
Dick

Natan,
Dick Rake is very correct. Depending on your work area temp.  You might cover your windshield and put a 100 watt incandescent drop light under it for a period of time, like over night.  Keep the bulb off the table.  Lexan bends very quickly in the 200 to 300 degree range.  It can be bent, normal (Southern), cold as well, 70deg.  There will always be some spring back.  Looking good keep at it.
BobN

Dick, Bob, thanks for the words of encouragement.

Working with polycarbonate is like anything else that requires experience, like welding, flint knapping or gem cutting, making pottery, forging and properly hardening and tempering a blade.  You just have to experiment and keep doing it.  Trust me making one windshield that is only a bit flawed is pretty good progress right there.  You'll get it.

Heat lamps are another alternative.

Just by the way:  One of the best known self-employed canopy builders is out of business.  Anybody who wants to really experiment and develop the expertise to do acrylic and polycarbonate canopies could have a pretty lucrative business.

Tom

Aviation tin snips cut thin lexan very well. I've cut a few pieces for forklifts lately. One had a sharp bend and I trashed the first sheet trying to heat bend it. 1/16" if I recall. Also, that bent one I did, ended up using ratchet straps and windshield urethane glue. Seemed to work well. The glue let go after a couple months though,  so that's another data point. Windshield glue doesn't stick to lexan a well a glass......