Trunk Rust

MY 69 nova has a rust problem in the trunk. The whole floor pan in the trunk is rusted and I was wondering what kind of shop I need to take it to to have that floor pan cut out and a new one welded in.

How bad is the rust?I have a 76 that had a rust problem in the trun k pan as well. I was able to sand it down and fix it wil a fiberglass kit. It was easy to do, but the fumes were terrible. I primed it and repainted when i was done and you'de never know it was rusted before.