Hey thanks for the ideas, very helpful!

Yesterday I tried to get a head start on the prep work and scraped most of the undercoat off the areas we'll be working on. Now it appears they won't interfere with the ribs in the front floor section once the undercoat is scraped off, and I can live with them running through that short section. That's just a first impression, we'll see if I'm right after we take some measurements and possibly string it/maybe snap some lines.

It also looks like....if a person really wanted to go wild with this idea, 2x4 wouldn't be out of the question it would have to run through the entire floorpan front to rear though. But that's really more work than I want to do, and probably overkill.