Prepping Factory Bumpers for Bed Liner?

I want to spray my factory bumpers with bedliner, I've done a lot of metal stuff. Bumpers, rails, racks, ect.. But never any plastic. I just finished my stroker build on the Jericho jeep and i wanna start with the aesthetics of this rig. Any tips on how to prep the plastic for bed liner would be great. There are a couple holes from aftermarket tag brackets from the PO i'll have to bondo. Is this an issue?

Just scuff it up with sand paper, 80g should be fine. Scuff it up especially rough around the holes you want to bondo, and use as little as possible.

Alright, that sounds like a plan. I'll sand them down and wipe them down with some solvent to remove the grease. Hope it turns out well!