I found another rust treatment product much like the one NAPA sells, but this cost much less. Sold at ACE 'OSPHO', it's $23 a gal.. Just clean off dirt and flakes then brush or spray on, paint the next day. I usually do a second coat.
I'm going to need something for my 763, not sure where it worked but it has a bit of rust on the under carrage. My sandblaster sure is going to have a work out! The main frame is pretty good, just some sections that are kinda nasty. Even if i treated it then hit it with the sand blaster for a good surface to work with may be an option.
