elcome to the 'Bolt! In addition to what Frank mentioned, I'll add to check where the front fenders attach to the cab, just in front of the doors. They're notorious for rusting there. If the truck's solid, it would be a good one to get. Tose 235s are good engines, with a little warming over with performance parts from Langdons or Patricks, they'll run with modern engines with relative ease. The only drawback is the gear that those 3/4 tons run, it's a little low for keeping up with traffic. Swapping in a overdrive can fix that.
These old Chevies aren't too bad to work on. If you can handle an old Binder, you won't have too much trouble with a 'Bolt mechanicly. They're very similar. And if you do have a problem, well, all you gotta do is ask. Someone here either will know the answer or be able to direct you to it.
I wouldn't want to give you a guess on a price without seeing the truck first, but around $3-4000 is the midrange for a '54 3600. That's for a well maintained driver.
And since Frank put up a pic of his, here's mine!
http://rides.webshots.com/photo/2097784960092261295mALOOE