I am not sure about the 67 but 68 and 69 each have diffent seat rail part numbers and they are different from any of the other seat rail part numbers. Looks like they are pretty car specific. I dont know if it will work or not for you - keep us posted.
Without knowing for sure which B-body you are referring to, my interchange manual says no. However, as a guy that can get things to fit, I am pretty confident that they can be made to work with a couple of new holes and some proper bracing and perhaps a little shimming. Keep in mind that this is a safety item in the event that you are involved in an accident.
Personally, I would put them up in the barter section and trade for some that fit properly and were meant to be there.
Either way will get you your end result - seats in your ride. Good luck!
i have a 1966 barracuda A BODY prostreet car,, i use 1972 cuda E BODY hi back buckets currently in my car,,i just switched the seat brackets i put the A BODY brackets on the E BODY seats,,im sure the floors in the B body are differnt then the A bodys,,,