i dont see why not, i used engine enamel to paint mine and drove them the same day
after three days ur not gonna hurt them just dont go bangin at them with a hammer or anything
7 days is really really long, mine said wait 24 hours, i thought that was a long time. i say go for it. 3 days is PLENTY of time for the stuff to dry. it should be fine.
try touching the back part of the caliper and see if its dry or if it smudges or smears. I would say you are good to go though, especially if its been out in the sun.