Auto body repair & detailing: rust on my chevy, nooks and crannies, rust paint

Question
i have a 1999 chevy 2500 truck with rust over the complete truck i the last owner plowed snow and i thing the salt that he used rust the complete under carriage of the truck i read about a product thats call rust converter ac-340 / 5 and rust away jell ac-341 / 5 do they work and if i spray the complete under carriage would that end my problem

Answer
You really picked a poor candidate for repair here, Terry. I would have the undercarriage professionally media blasted, then sealed up with POR-15 primer. Rust converters and gels really don't work on the scale you are proposing. The underbody has so many nooks and crannies that it would take a month to try to do all the things you propose by hand, lying on a creeper. I picture you covered head to toe with dripping acid, rust, paint and scale. Not pretty, and darn sure no fun. Once restored, I would have the undercarriage coated with parrifin based undercoat for additional protection.