JW51,

I used CLR and a BBQ grill brush on the heavy rust and a gray scotch brite pad on the rest scrubbing till well foamed up and the pad slid around easy without sticking to the truck and I also used Krud Kutter rust remover that seemed to work great, then rinsed and looked at progress then if it needed more I did it again, Managed to finish the truck the other day,FYI your hands and fingers may get irritated by the chemicals for such a long period of washing and scrubbing so rubber gloves are probably needed...just saying from experience.
Here is a pic one side done and sprayed with satin clear and the other side like it was before...

http://i10.photobucket.com/albums/a...ruck/clearcoathoodfender_zps4e03da8f.jpg

1946 Chevy small block truck
1941 Chevy 3/4-Ton -- sold Sept. 2014 | "Ole Rusty" | In the Stovebolt Gallery