I'm new to all this, but look forward in learning from the Pro's. I just made my dream truck a reality. I happen to have a very nice 1950 5 window 3100 Pickup in very orginal shape very little rust and running.....The vin number tells me it was manufactured in Kansas City in July of 1950. All the old paper work shows the truck as a 50, but many items on the truck tells me it may be a 51. ie Vent windors on the driver and passenger doors. Is that not a 51 change ? I guess the question is when or which month of year back then did the assembly plants change to manufacturing the next years model.