Greg Fordahl is in the Seattle area. He is the 944 guru and has a shop that preps lots of 944's. He is also a GREAT driver and suspension guy for your setup.
I would go to him and discuss it all and look at various seat options with him first. His advice, both now and forever, will be invaluable to you, IMO.
The only issue I have with bolting to the floor is that, in a big, side impact type incident, I have seen the floor buckle from the G forces of the driver's weight and allow the seat to move enough, at the top, for helmet contact with the cage. I do not know if that was only early cars (three examples) or not but it was obvious that the floor pan buckled.
Good luck and do all your safety stuff to the highest possible standard.
Big Dog
