In this case, the brackets should be removed from the model name:
http://www.imcdb.org/vehicle_106073-Chevrolet-C-Series-1971.html
And it should be narrowed down to a C-20.


Speaking of narrowing models down, this one:
http://www.imcdb.org/vehicle_554532-Chevrolet-C-Series.html
... is a 1969-1970 C-30.