Little help? Hi-metal R heat shield for perf. trans.

[dur]

Hi, I'm hoping to try to make a heatshield that can stick onto the clear canopy rather than having a parts swap (i'll figure out how to hide it in the fighter later!)

I was about to start sanding/cutting/milling away at my heat shield, but then I thought, I'm sure there's a way to do this with a two part mold so that I can get a perfectly conforming heatshield rather than me trying to guess!

Does anyone have any advice on how I would go about this project? I'm thinking if I make a mold of the heat shield and then use the clear canopy as the other side of the resin mold, I'd be able to make a heatshield just right.