I bought the bags already missing the leather, so I was kinda stuck painting them! Did not paint over the leather.
OK, so what I did was wipe the bare plastic with paint thinner, hand sand everywhere (except chrome) with 600 grit sandpaper. Wiped them again with the thinner, and sprayed them with one can of adhesion promoter over both bags.
I followed this with one can of sandable primer over both bags.
Let it dry overnight, then sanded the primer smooth with the 600 grit.
After that, I laid about 4 coats of color over both bags. I used 2 cans of duplicolor "perfect match" if I remember correctly, which is a really close match to the stock paint with just a little metallic to it. I'll have to get the paint code from the can, but they had 2 metallics, one cap looked basically black, the other looked way to silver. I used the black one.
Followed the color with 4 coats of clear, same thing, 2 cans over both bags. Last coat needs to go on pretty thick without running it so It has a nice gloss to it instead of that "overspray" look. After they dried, I mounted them up. I need to get some nylon washers for the hinges since the leather isn't there to take up the space. They wiggle around a bit right now.
Hope that helps!!