I would not recommend an adhesion promoter over already painted parts, even if you scuff them (which you should - I'd use a white scuff pad & Presta Scuff Stuff). As far as I know, adhesion promoters should go to bare plastic only.

Get a matching interior paint from any automotive paint store or jobber. Interior paints typically don't use a clear over them. If you do that, it won't match the rest of the interior.

Apply a nice medium wet coat, let it flash, lay on a second medium wet coat. Done.