I can't say as I've ever had the pleasure of coating pop rivets before... but see very little in the way of problems for you with them. I'd certainly suggest not doing bolt heads for the reason that they will be under a tremendous amount of stress during your application. As for the sandblasting.... if you have an option to use one for surface modification (adhesion) it always best. Did you order any chromate then? Just curious. Seems to me to be a part that's going to see a few bumps and bruises, so you might want to go that extra step to assure a good grip of the powder. Good luck with your new "toys" on the 2nd and by all means... we LOVE pictures! Oh.... by the way,
thank you soooo much for reading the posts before you ask, it's a good thing
..... Russ