A few Chevrolet C & K Series pickups were given the wrong years. This one, made in either 1971 or 1972 was incorrectly listed as a '68:
http://www.imcdb.org/vehicle_121097-Chevrolet-C-10-1968.html

So was this one made in either 1969 or 1970:
http://www.imcdb.org/vehicle_571814-Chevrolet-C-Series-1968.html

I saw a few others, so I'll have to keep tracking them down.