67 dash

I'm working o the dash of my 67 GTO. I've got the gauges out, the glass needs cleanng. I'm afraid to use glass polish for fear that they are plastic not glass. Are they plastic or glass?
Thanks
LET

Plastic, possibly polycarbonate. Avoid using paper towels, synthetic material, and harsh chemicals (including glass gleaner with ammonia or alcohols). Try hot water with a mild soap, and a hot water rinse, dried with a cotton towel. It may take a few cleanings to get them truly clean, but is worth avoiding the microscopic scratching and dulling.

Any polishing of the plastic should be done with a rouge wheel and mild abrasive, just like opticians use to make and polish lenses for eyeglasses.

Thanks so much for your help Bowtie !! I thought they were glass at first so i tried a test spot on the edge with some glass polish and it dulled, so i figured it was plastic. The big piece has what looks like some rust stain. The rest are pretty good. So i can safely use a rouge wheel and glass lens polish?

Plastic lens polish, such as water-thinned red rouge. I believe it's a lot softer medium than some of the silica mix normally used for initial stage glass polishing. A cotton wheel is going to be critical, and very low force since styrene and poly-type plastic melts a lot more easily than glass.