Very good information, thank you gentlemen.
So far I've been happy with whatever clear acrylic I've found, I guess the most usual brands here are all pretty similar.
I've also noticed that they dry hard, and ideally should be sanded after 24h from spraying. (impossible for me) But with molded parts, it's a little less important. And we have a long & dark winter to sand & polish. L
Phil's stuff, you can rub out later. If you only wait 24 hours, it's easy, but it is definitely going to keep shrinking after that, for a good week or so, even at summer temperatures. Again with molded parts, it's like a car, everything under it is a constant thickness, more or less, so it is not quite as big an issue as over wood.
DAU-75/DXR-80 is *diamond hard* after about a week, and I recall trying to fix a few things after about a year, and I ended up going down to 1000 grit just to break the glaze, just to get a small scratch out of it. We haven't use that around here for decades now - although the same diamond hard surface also fends off small scratches, etc, much better. Phil's stuff is better, and you can still get it most places, as long as you are not subject to the unaccountable hitlerite bureaucrats of the California Air Resources Board.
Brett