I can tell you what my truck weighs...
I have a 1953 Chevy 6400 flat bed (so it would be a 1st series). I weighed it over at the local cedar mill when I bought it. It weight 6900 lbs with a homemade bed and had half a tank of gas in it.
I also found a webpage that has some specs for the Chevy vehicles (it also has some service manuals and the like).
1954 Chevy specs
