The rear corners were very badly rusted, while I had the roof off I made sure to fix it. Cut, weld and paint.

New tool, Rotary Hacksaw very viscous tool for cutting metal, beats using the cutting discs. $35

Rear right corner of the tub, lots of bad rust, been putting this off for a while, finally got into it.

Made up a template out of cardboard, the hole it where a nut needs to be to attach the roof.

Mark template onto steel.

Cut out all of the rust.

Tacked the new piece in, all fits well after some touch ups on the bench grinder.

Welded into place. Sits flush so shouldn't affect how the roof sits.