Easy fix for interior rust holes?

[personaltrainer]

Okay. I took out the carpet/insulation in the entire truck today. I was not totally suprised at what I found - just wished I hadn't. Yup - rust, rust holes to be exact. I have 3 holes that are about 4" x 4" if I were to make them square. I do not have the tools, knowhow, or space needed to do this thig right and replace the floor pans - SO.... given those perameters what should I do? Fiberglass? (not flexible enough). Bondo? (not water proof) what else would be a good idea and should i prep? - with POR15 or can I just use the rust inhibitor from the parts store?

BTW these 3 holes are in the cargo area. I also have a couple of smaller holes in the drivers side floor nearest the door. The worst being a long one and it measures about 1"x 10"

Thanks. sorry for the long post......

 

[6.2 man]

If you are going to cover them up again with carpet or mats ? I would just get some sheetmetal and cover tem that way and rivet them down . Maybe run sillicone beads under them. If they cover the ribs maybe hit a wrecking yard and have them cut thos pieces out of wrecked Blazers .

 

[84mudmachine]

I used sheet metal, then put a coat of fiberglass bondo on bothsides and then coated that with some roll on bed liner.