I found these videos which might work well in case I decide to remove the stickers under the clear coat - looks very easy even though this is metal and my parts are all plastic:
LINK to video "removing decals under clear coat"
And this video has some interesting tips for painting plastic
LINK to "painting plastic car parts"
I can't comment about the tips from the paint company. I just thought the 3 step process (prime, paint, cover) seemed like a reasonable plan but I know very little about this stuff.