I'll start by saying I'm the most clueless mechanical/spannering minded person. Mine was for a rocket. Buy a sheet of Polycarbonate.
I've no affiliation to these people, just whom I bought it off. Size was a guess by me but was more than adequate for the rocket, if your good at measuring/working out you can obviously buy it for less. I bought 2 pieces, in the end didn't need to, just used one. Guess you might be able to get a smoked colour one, clear is fine for me.
www.theplasticpeople.co.uk Products Min Order £24.99 - To avoid a small order surcharge increase your order value by Option - SOL SURCHARGE CTS - Cut to Size Polycarbonate Colour - CLEAR Gauge - 4mm Length - 1300(mm) Width - 500(mm) Sub-Total : £58.50 Next Day Standard Delivery : £8.50 Total : £67.00
How to do it, buy a massive piece of hardboard this for me was an iterative process as on the rocket the screen base needs to be on a curve. I used wallpaper at first to try and get the general idea of what I wanted. Used this to cut out the hardboard version, my first one was way out threw it away after using it to make adjustments, rinse and repeat as many times as you need to I think mine took about 4 or 5 hardboard versions. Then you need to fit it, meaning on the rocket drilling holes in the bonnet, get some bolts/washers/nuts and attach it, this was obviously the no going back part ie those holes are in your bonnet. So fitted the hardboard windscreen, went out for a test drive (looking an idiot) thought it was fine. So used the hardboard as a template for the proper polycarbonate version.
Attached that tightened bolts up and went to Switzerland and back in it the next week, was fine, I also sit quite tall in the car so mine was quite high, alot higher than the RTR provided ones.
On a private road I did a max speed run and it didn't shatter/rip off or do anything bad and as I say mine I think has a 12 inch height so it's quite a bit higher than the RTR one.
I cannot stress how hopeless I am at doing this stuff, but even I found it relatively easy, and keep the hardboard final version and you can knock a new one out if you ever break it for whatever reason.