Hi, hope your project's comin along fine. I've restored cars for many years and have found an excellant product that works very well on surface rust after cleaning the loose stuff off with a wirebrush or wirewheel: Rust Destroyer <a href="http://www.rust007.com/html/rust_destroyer.htm" target="_blank">http://www.rust007.com/html/rust_destroyer.htm</a>
This stuff is guaranteed for 5 yrs to stop rust and I have found it working much longer, some vehicles I treated with this stuff 12 yrs ago still have no buubling where I applied it. Its also available in spraycan form for less than $10 per at dept stores in US, up here in Canada I can't seem to find the spraycans anymore, but the liquid cans are still available at certain marine shops that also swear by its quality.