The main difference in the cab is the dashboard. The Chevrolet has a
V shaped geage cluster , with the Ammeter, Gas, Temp, and Oil gauges across the top of the V. The GMC has a more or less
rectangular gauge cluster, with all of the gauges being circular and set in a die cast panel. There are some other differences in the shape of the dash due to the differences in the guage clusters, plus the GMC would have a provision for a radiator core support brace that is not present on the Chevrolet (exept Suburban/Panels) on the firewall.
