Floor repair options?

[JayBee]

Hello - I have had 2 things happen lately that finally prompted me to pull all the seats and carpet up in my Century.
1. I nailed the throttle and the driver's seat pulled out of the floor sending me to the back of the boat which happened to continue accelerate at full throttle.
2. The center section of the floor has always been a bit soft, but last week it dropped about 3" below the side sections of the floor.
So, I pulled it all out. The plywood seems to be in solid shape - but it is really dry and anywhere there were screws they've pulled out. The reason for the center of the floor dropped is actually the fact that long strips of wood that support it pulled out of the stringers. The side sections of the floor seem to be glassed in along the sides where they meet the hull, and the area underneath is foamed. I have had chucks of foam that have broken loose appear in the bilge since I got the boat.
What is the best way to restore/repair the floor? Should I cut the floor sections loose along the sides and remove them to gain access to the foam? Should the foam come out too? Is there anything to treat the wood with to protect it?
I may just replace some of the center support flange screws to get the center back level and stick it back together for a winter project.
Thanks,
Jason

[JayBee]

Here are some shots of the floor:
Floor (http://webpages.charter.net/jlbarnes/boat/floor.JPG)
And the supports:
Center Support] (http://webpages.charter.net/jlbarnes/boat/floorsupport.JPG)
I also discovered my gas tank mounts are both very loose. The tank was mostly held by the filler hose and has baged against the hull on both sides:
Fuel tank (http://webpages.charter.net/jlbarnes/boat/fueltank.JPG)
The 27gal fuel tanks looks like something built for a genset rather than a boat!

[BrendellaJet]

I cant beleive it, I just wrote out my response and now its gone....
Anyways,
The red piece in the first pic, is that the floor(called a flase floor)?
If its really dry, replace it. You can treat it with resin or resin to protect from the moisture. If the side pieces of the floor are still in good shape, leave them there. You can drill some 1-2 inch holes in those pieces if you want to replace with expanding foam, just make sure you have plenty of holes drilled to give the foam someplace to escape in the event you use too much.
Nows a good time to check out the stringers too. If they are not solid, none of the work you do will be worth while(although you may beable to save your summer...) If they are in bad shape though, they will need replacing. If they are sound, just remount those strips and you'll be in business.
Try to find some saddle tanks, and get rid of that bow tank. You'll pick up a few mph at least.
Lets see some more pics of the boat and motor.

[JayBee]

Yeah, I was planning on spending some time looking at the stringers. But, I seem to remember them being completely glassed in - not just at the ends.
Here are some more pics of the boat:
Boat in the water (http://webpages.charter.net/jlbarnes/boat/BOATINWATER.JPG)
The engine is pretty boring looking compared to most boats on here:
Chevy 396 (http://webpages.charter.net/jlbarnes/boat/BOATEN~2.JPG)
And here is a last one that shows my dad running it so I could get roost pics:
Taking off (http://webpages.charter.net/jlbarnes/boat/DSCN0068.JPG)
Thanks for the input!
Jason