I like Zero Rust. There is a review on the tech pages here on the stovebolt. It can be brushed or sprayed and doesn't have the "nasties" as in POR-15. Check out their page:

http://www.zero-rust.com/

Best thing is I found it locally at KMS Tools in BC. I don't have to wait

A day without laughter is a day wasted- Charlie Chaplin
When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired.
1948 Chevy 2-Ton