After getting all of the seats and flooring up, I did a check of the subfloor and decided that it would be best to add some additional support to this almost 20 year old bus so I wouldnt have to deal with it again in a few years. Well worth the extra money for the 1/8" 4'x8' sheets but I did have to break out the metal drillbit to predrill the screw holes due to the metal subfloor under the wood subfloor.
I also picked up some really nice vinyl flooring from the local hardware chain (Menards). Ended up being 88" wide wall to wall between the heater piping and the side, and an extra few inches towards the back where there was no heater. Total was around $200
Once the flooring was done, I was able to recycle the wood from my city bus project to build the new benches, at a more managing size with extra aisle clearance. Once these were in, per DOT i had to use some hefty screws drilled thru the subfloor to hold them down
Next time, I'll post of photos of the benches and the seat back as I get closer to prime time