If you're going "Show Car", or even attempting to be the Show-N-Shine" big dog ...... You need to find a chemical resistant, quality urethane product. Then scuff and shoot the parts with it.
Why spend the time to prep and paint such difficult parts if some simple chemical agent, I.E. brake clean, carb/throttle body cleaner, simple green, that Purple Stuff or some other common agent will ruin your work when you least expect it too?
Call "Space Age" those guy can and will mix up what you need in an aerosol can...(or two or three..) or sell you a pint/quart of it.
Good luck to you!
Keep us informed on how it all goes, please.