I have the same problem. Iam getting as much rust out of the pits as possable. Then Iam useing Zero Rust as my first coating. It will prevent the rust from comming back like POR15 dose but its sandable. Then I get a can of High Build primer filler and spray it pretty thick in the pitting area in several differnt coats. Then I wet sand it with 220 git paper and repeat with anther coat of Zero Rust and Primer filler and wet sand again til the pits are all filled in. Iam sure there are many differant ways of doing it. I used this process last weekend on areas that are difficult to use body fillers.
Good luck!
Good luck!
