Prepping a Rusty Body Panel for Paint

[Ehlien]

So I have this truck from OK that the sun has baked the paint off. Now its cracked and starting to show minor surface rust peaking through. I put a 3M disc on it to start taking it down to the bare metal but in places it has some minor rust staining or very, very minute surface pits the disc will not take out. How do I effectively neutralize or prep these areas for paint??

 

[34pickup]

Phosphoric acid. Body shop supply stores carry it. Then use baking soda to neutralize it.
Then you can get a high build primer thats like spraying on bondo to fill the pits.

 

[Ehlien]

Good tip..I have some PPG DX579 metal cleaner which is phosphoric acid base but when I use it I leaves a lot of surface rust a it dries. I found they have a second product dx520 to apply right after that neutralizes and coats however baking soda might just be the simpler and cheaper ticket.