I’m painting a new aftermarket Subaru Outback 2013 bumper cover at home using proper auto paint & 2k clear.

The part comes “primed” & part of it does not get painted to maintain black pebble plastic finish the factory designed the bumper to have in that area. That part looks seperate; almost like a plastic overlay.

I know “raw” bumpers have a whole cleaning process to get paint to stick right. A few questions:

1. Do I need to use adhesion promoter since it comes primed? Flex agent to the paint?

2. I know I paint the mounting parts and maybe wrap around; any reason to paint any of the back?

3. I’ve successfully painted stuff at home & can wet sand & compound out any defects in the clear - any other tips are appreciated!