Yes, Coolamundo VaFT!! And welcome to the Stovebolt Page!
Before you do anything else, be sure to email us one of those photos and the writeup of the truck for our Gallery.
And speaking of the Gallery, have you been to the other parts of this web site? We have a great Tech Tips (well, it's getting there) section, feature stories, extensive list of old truck-related links and other useful and entertaining info to help you on that big truck. Just use the menu bar at the top of this page to go poke around the rest of the site.
Also, we have a pretty good search function. This particular Bulletin Board has been on the site since 2000, and the web site itself has been online since 1995, so chances are pretty good we have the info you are looking for. Also, as you read this Tech Tips, we're one of only a very few old truck web sites that has info on the bigger trucks (Along with Jolly Goodfellow's '60-'66 site. There may be others, but Ours and Jolly's are the only two I can think of. Jolly hangs out here, too.
And you have Tom Brownell's book -- great! Did you get the new version? The new version has a section in it for big trucks.
Now, to get down to business, as Kool and the others said, about the only stuff that interchanges with the pickups on the AD trucks is the cab and all the stuff in or on the cab (Interior, doors, weather stripping, etc) hood, fenders and chassis are different. Engines, if original, on the 6000-series will be a 235 (One of the other guys can tell you when the 261 became available as an option for the big trucks -- I forgot). The 4-speed SM-420 transmission is the same as can be found on the 3/4-tons and up.
I have a 4000 series truck (Ton and a half that's in the bulletin board logo at the top of this page) that I'm restoring and so far, I've had pretty good luck finding everything I've needed. I think the biggest challenge has been the parts for the rear axle (I have a 2-speed from a '51 2-ton), but so far, so good! On wheel cylinders, axle bearings, etc, NAPA has been my main source. Everything else I try to get from American Classic because they sponsor the site. Jim Carter and the other vendors listed on the Links Page are good, too. We have some of them flagged for having big truck parts too, I think.
Anyway, you've come to the right place for help with that truck! We've got a good crew here and they'll help you out. You're off to a fine start -- keep the questions coming!
Regards and welcome!
John Milliman