There's no way to do it right without cutting that out and welding in new. You can patch it with lots of stuff that will sort of work but eventually will be a Flintstone car. If you want do do it cheap just put some carpet over it and don't drive it in the rain. Sell it when you get tired of it.
I plan on using new floor or half pans ........ Also I am removing all the bad metal........Just looking for tips on how to attach without welding......( do’s and don’ts )It’s not going to be a show car so not really worried about the look just that the floors are in ........however I attach it I also planned on sealing every new seam........ Thank you again for all help and advice......