[snbush67]

I am no expert but I did do some internet research. The best way is to have a huge oven that would heat the plexi in and a form ready to slump it onto. I am assuming that is out of the question?

They really aren't hard or complex bends, but they are large bends. You can do it, but not easy and or not cheap, if I was doing this I would make a wooden buck using my original glass as a template. Then I would clamp down the center and use heat guns and work my way out to the edges. The problem is heating the large surface area and clamping, bending etc. when you only have two hands. You'll need helpers.

Another option would to use your original window placing it upside down and bend it cold to clamp the center and then using heat and gravity to slump the plexi glass into the original window, but I think it would be risky to your original glass. Perhaps you could build a support for the original glass.