Frank,
I may be wrong here, but is Lexan self-extinguishing if it catches fire?
Also, what are the temperature limits of this material, if it is anything like Plexiglass, it softens when you heat it up, that's how they form it to build things out of it.
What I'm trying to say here is that while there shouldn't really be a lot of heat in any electrical enclosure, but that needs to be taken into account if you are using thermo-setting plastics.
Just a thought off the top of my head.
