Lenny, The main thing it tells ya is whether or not your frame and cab were married at the assy plant.
It's a partial vin. Check the frame # against the vin # and they should be the same except your vin # should have 4 more charaters in the middle.
As far as what they tell you, the first character tells chassis designation C=2wd K=4wd The second character tells engine designation E=v8 S=6cyl The 3rd character is a place marker, and it's probably a 1. The rest should be numbers and that is the vehicle or production number. That's on the frame.
On the vin on the driver door jamb the extra 4 characters tell GVW range, model type, model year and assy plant. Oh, and
to the board. If you need help decoding your vin just holler.........