I used a two part industrial enamel paint from O'Reily's Autoparts. One of their local stores has an automotive paint division that sells to local body shops.
Can't remember the color name, but it is close to our Federal Safety Yellow (don't tell Geo it's not Elec-Trak yellow
). It was about $200 per gal with the reducer.
Our local Tractor Supply carries an industrial paint for about $26 per gallon. It did not open until after this restoration.