Hi Bob
Regarding your request for advice -
I put a fully clear roof on my first plane, a Sav classic with the slats, back when they came in alu with a little trapezoid shaped window. I thought the all clear roof would be good for visibility etc. but later I hated it because it got so damn hot under it on long flights, especially in summer, so I ended up putting the origional back in with one of those stick on shades on the window.
Later on I have put an aluminium roof on a VGXL, From memory I used 20 or 25 thou 2024 sheet and just used the plastic roof as a template. On the underside I insulated with 16mm black sponge rubber from Clarke Rubber, then covered with the grey light weight carpet. Worked well, no burnt head or sun reflection on instrument faces. I also did another one with an alu roof but with the smaller window insert like the older Sav's had. I have seen painted lexan as well so that can be done, but I would prefer the alu replacement instead.
Hope this helps
Rick