what to do with this rally dash?????????????????????????

When I re-did the dash on my 64 Valiant Conv I used the bright silver (engine paint color for the 50's mopar flathead six). then a day or two later I used a matte finish clear urethane over it and it came out looking like the rest of the dash that had not been touched. That was 20 years ago and still no peel or fade. Try it on a piece of test plastic from a hobby shop.
As far as which color to do first-always do the lighter first as the darker will cover it but white(light) has a hard time covering black(dark).