I have a 94 with the same issue. For an interim fix, I cut out the floor and from the inside reassembled using sheet metal. This year, I plan to remove that and fab a better bitting box that I can use for some under seat storage. The biggest issue that I encountered was reattaching the seat mounts for the backseats. Fabricating you’re own will require more careful planning to ensure you can bolt your seat backs correctly. Good luck!!