Dave:
I removed 1 floor but not the 2nd (right side). There is no real reason to remove them (read that as required to remove for sequencing the build). I took my first one off because I thought I might modify them with screws vs rivets but as I got further along, I realized I didn't need anything under those floors so, rivets went back in. Put off the decision until you have your systems defined and an idea of your wiring needs. You may later decide to install a conduit or some items such as antennas or relays under the seat. You should be able to install a conduit from the baggage side of the bulkhead, those floors are easier to remove in my opinion (7A builders will be removing those to install steps). I installed all my wiring, relays, electric trim and terminals with the seats fully riveted in place.
As previously mentioned, the baggage floor and aft seat floor share a rivet line and the plans indicate the assembly order as optional (baggage over seat floor or vice versa). I went with baggage floor over the seat floor and later regretted it when installing the center flap bearing block. It'll fit easier with the seat floor over the baggage floor.
Jekyll