I recently narrowed down a few Ford F-Series pickups and cab & chassis trucks:

This one was made sometime between 1970 and 1972:
http://www.imcdb.org/vehicle.php?id=515103

This 1976-77 F-Series was only an F-350:
http://www.imcdb.org/vehicle.php?id=110973

This one was made between 1973 and 1975:
http://www.imcdb.org/vehicle.php?id=480941

This one could've been made anywhere between 1973 and 1977:
http://www.imcdb.org/vehicle.php?id=468032

This one is without a doubt a 1965:
http://www.imcdb.org/vehicle.php?id=418902


I also spotted an Argentine one from the early-1960's that I can't find right now.