I believe they are 68 barracudas.
67 will have “Plymouth” lettered emblems across the front header.
These cars do t have that. Also in Dec 1967 they would be well into the 1968 model year.
May be hard to see in this pic but on the lighter (white?) cars I don't see any marker lights as found on '68's.........
(I blew up the pic a little, still didn't see them)
Regardless, still a cool old photo!