Question I'm sure I don't really want answered...

[rgunlock]

Had some bubbles under the paint in the front roof corners of my cab. Sanded back the paint and body filler to find some rust through and signs of a bunch of prior welding. I cut out the obvious bad sections of roof skin and see that there is pretty heavy rust on the inner roof, although I don't see signs of it from inside the cab.

I'm not building this truck to flip, so I don't want to have more rust through within a few years. Not crazy about the idea of replacing the roof either. I've gotten decent results in previous body panel patching, but I'm no pro. The rest of the cab appears to be in good shape. I can see what appear to be good repairs in the floor and cab corners, rockers, etc. all look good although I haven't stripped the paint from them. I don't see any more obvious problems with the roof skin, although there is no telling what else is hiding under the body filler and paint.

Looking for suggestions on saving this roof. Or here's that question, should I be planning to replace the roof?