If you're going for the 90's conversion cab look, go with acrylic over the CP.
It is not as shatter resistant as Lexan, but it more optically clear, and harder.
If you want a classic cab look, get .010" Lexan laminate over your CP art.
That, or silkscreening directly to the metal, is what was used on almost all the dedicated cabs.
If you look at all the classic round-front Williams cabs (Robotron, Joust, Sinistar, etc...) they all have Lexan overlays.
Likewise alot of the classic Midway cabs had the same thing (Tron, DOT, etc...)
The pebbled finish on the Lexan overlam helps it hide the scratching that is so visible when the surface is polished.