1st Paint Job

fill the pits rush etc, then zinc prime it, then put on a good few costs of 2k primer, then sand it down and paint it... ;)

1=rust converter or etching primer if surface is still showing rust
2= good quality sandable primer
3= quick sanding to check level and pitting
4= bad pitting? fill holes/sand[220 grit]
5= reprime with sandable primer
6= refill missed places/sand[220 grit]
7= reprime/sand again [220 grit]
8= everything level and smooth? one last prime coat
9= finish sheetmetal with 320 grit paper
10= Paint the color
This may seem long, and you could skip some steps
depending on the quality of paint job you can live with. Painting is 90% surface prep/10% finish color. On cast parts you don't do the fill, as then the cast looks smooth, not like cast iron.
Hope this helps.