So my Duster is mostly Rust Free...
Agree with barbee6043 on the cleanup process. After cleanup, consider painting the surfaces with POR to keep rust in check. Definately remove the roof rail gutters and inspect them. My 74 had a vinyl roof and the rust wasn't too bad on the top, but the drivers side rail (covered up by the roof rail when I inspected the car) was a mess. I had to find a donor roof rail to replace that section and it was a pain. And if you do eventually replace the roof, make sure your donor is a 72-76 Duster roof that takes the one-piece headliner.
Agree with barbee6043 on the cleanup process. After cleanup, consider painting the surfaces with POR to keep rust in check. Definately remove the roof rail gutters and inspect them. My 74 had a vinyl roof and the rust wasn't too bad on the top, but the drivers side rail (covered up by the roof rail when I inspected the car) was a mess. I had to find a donor roof rail to replace that section and it was a pain. And if you do eventually replace the roof, make sure your donor is a 72-76 Duster roof that takes the one-piece headliner.