Floors look savable to me but i am a budget build kinda guy.I would take a wire wheel to them from the inside if it's just pinholes you can use all metal filler, or duraglassthen coat it with POR15 , you just need to get all the rust scale off (don't grind to bare metal) as the POR is made to bond to and convert the rust and make it inert. Worse case i would weld in patches and not a full pan as it only looks to be bad in the wells. Really depends on what level you take the restoration to, not all cars need to be taken down to the last bolt, body off concourse restoration. Heres the equation, the more you take it apart, the more, money, time and space you will need to get it back together. Body looks like just patch panels, have them check the front and rear window channels too, they were a problem area, more so in the 66-67's and vinyl top cars as the false fastback fins helped hold the water on the rear deck panel especially if the car was raised in the back at all. Thats also why so many of the trunks are rotted out in these cars.