We use PPG DX 1791 with DX 1792 wash primer on all bare metal. Then K-36 high build primer followed by epoxy sealer and PPG concept single stage paint with 2021 clear mixed in the last coat. Always ask for product information sheets when you buy paint materials. There are many other ways to go but the most important thing to remember is to use an acid etch rust inhibiting primer first followed with a two component high build primer. Your paint job will turn out alot better with good quality materials and it will last a lot longer. I painted 2 Tokheim 36B display pumps 6 yrs ago and they have been outside in Iowa weather ever since and they still shine like the day I painted them. And absolutely no rust. Email me if you have any questions, I've been in the body business for 13 yrs.
Chad Clapper
Clapper Restorations