How do I get rid of this rust in the trunk?

The trunk of this car was covered in POR15. I began removing it and had to do a lot of rust repair to the passenger side of the trunk. The drivers side metal feels solid but I can't seem to get rid of this pitting that was underneath the POR15. The metal is strong so I don't want to go through

How to prevent rust with old cars and trucks: The solution might be easier than you think!

How to fix rust on boot lid & stop it reoccurring? - Body, Interior & Styling - MX-5 Owners Club Forum

Vintage storage trunk ideas when it comes to restoration - Tidylife

Trunk lid rust help Chevy Tri Five Forum

Curbside Corrosion: Deep Rusty Thoughts - Curbside Classic

How do I get rid of this rust in the trunk?

Surface Rust Repair How to Fix Small Rust Spots On Your Car or Truck

Rear hatch and tailgate RUST repair!

How to Clean Rust Off of Antique Metal Trunks, Hunker

Datsun 510 Rusty Trunk Floor Repair

Removing Iron Rust Spots From Vehicle Paint

Car rust guide: how to remove and prevent it

Repairing pinch weld rust

Car Rust Repair: How Much Is Too Much? (and How to Fix It) - CARFAX