['68OrangeSunshine]

Yeah, you're right, if it's a two wheel drive, the truck technically isn't a K/5, it should be a C/5. Problem is most folks don't know or care about the differences in Chevy truck numerology. So if you say C/5, they're thinking of a huge Lockheed USAF transport, the C-5 Galaxy. It doesn't help that Chevy only produced ''K/5'' fender badges regardless of a truck's having one or two differentials.
Also it's funny that the Chevy Blazers are called K/5s, but GMC Jimmys are K/1500s. K/750 would be a logical designation, but GMC didn't buy into it.
Originally, Chevrolet Division had been planning on an actual 1/4 ton vehicle, in the size and weight class of the Jeep, IH Scout, and early Ford Bronco, to be called the K/5 Blazer. Somewhere along the line, that design got scrapped when someone got the bright idea to make a light-enough sport utility vehicle by cutting back the frame of a haff ton shortbed fleetside from 115'' to 104'', blending in the Cab and Bed, deleting the hardtop for a convertible, and matching the body panels to the new size.
Instead of being stuck in development hell as the 1/4T mini-truck was, they were able to get it on line for release with the 1969 Model Year trucks.
They sold like hot cakes. GMC went on production with the Jimmy in MY 1970.
Dodge copied the full-size rig concept with the Ramcharger in MY 1974, but Ford Broncos didn't go full size until MY 1978.