Yes, he plans on leaving the seats in the car. He would like to order new foam for them. That is why he is wanting to know what they came out of so he can get the right stuff.Head rests were OPTIONS in 1966 and 1967, as well as 1968 cars built before January 1, 1968. At that point, they were a Federally-mandated part.
Those seats were built on April 8, 1968 (4-8-68 on the tag).
Does he plan on leaving the seats and console in the car? Hope he does, because you could order a bucket seat interior WITH console, even on a four-door "C"-body back then.