Tire pressure? Air shock pressure?

Ive owned 2 Dusters, that had the upper mounts ripped out when I bought them. Definately, get a new set of leaf springs! I believe they were Monroe's. Fill lines were melted when I got both cars. I used some of my "Vocational Ag skills" I learned in school to weld them back up!
If you have to run them for awhile, I'd start with 30psi and see how it stopped and rode down the road for a few miles. Then, adjust as necessary...