https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=915938&page=all

From above
Originally Posted by tclederman
There was no long-bed option for 1947-1955 Chevrolet Advance-Design 1/2 ton pickup trucks. So, there was no short-bed nor a long-bed in those 1/2 ton trucks (those terms are meaningless in those years).

3100 and 3600 trucks came standard with a 3-speed transmission (as posted above). A 4-speed transmission was a factory option (as posted above). The 3800s came standard with a 4-speed.

GMC New Design (47-55) 1/2 ton trucks in those years had a long-bed option in the 1/2 ton trucks (model 102 vs model 100 - in all ND years?).

Originally Posted by Brad Allen
Agreed here Denny. The more correct statement would be the standard transmission is the 3-speed but the optional 4-speed is a very common upgrade of that time. Here in the west I have never even seen a 3600 with the column shift three the 4 speed is/was the preferred way to order or spec the truck. I would also agree that about 1/2 the 3100's here are equipped with the 4-speed. I like Denny purchased my truck from the original owners family and it was factory original with the 4-speed. Here on this 1950 salesman order book you can see it was a $50.00 option, I think option is the key.
http://www.flickr.com/photos/advance-design_parts_co/8335509814/in/set-72157631872034068

RPO 318 4 speed available in 1949 3100
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