Nick, Find an automotive supply house and talk with them about what they would suggest. I could give you part numbers and my process for applying them, but it wouldn't help if you can't get the products....
If you are interested in my process it is as follows.
-Bare metal
-Rust repair/metal work
-DP40LF Epoxy primer
-All body work. Evercoat body filler
-Evercoat Slick Sand ( cheaper than K38. A sprayable body filler almost)
-Block with 80 touch up body work
-PPG K38 Block with 220 dry fill minor imperfections with body filler
-PPG K38 Block with 320 wet
-Wet sand with 500
-DP40LF Epoxy reduced with DT870
-PPG DBC base coat
-PPG 2002 clear with DFX11 hardener and reduced with DT 885
I have been spraying PPG product for 30 years and they do work well if you follow there procedures.
Hopefully your painted knows of what products to use. If he doesn't, do you know a painter that knows the automotive products that can do the work for you?