inner door clean up?

[69-nova]

hey everyone. im building a 69 nova and im starting to pull the panels out of the shed to start putting them on the car and gettin body work done. so i pulled out the drivers door and did two patches in the corners. know im trying to figure out a good way to clean, kill rust, seal backside of patches, and paint inside the doors so rust woulnt come back. Any info is great. Thanks jeff