As Jeff alluded to, I know at least something about these trucks.
First off, take a look at my website:
www.GMCSpecialEditions.com
If this is a truck you want when its done, then go ahead and restore it. The big parts are available (nice used bed, new front clip, drivetrain parts, etc...) to make it better than new. The special Beau James parts are rare, but if you're patient you can find them. They had special bed rails, floor mats, tonneau cover, factory fog lights and the decals on the side of the bed. The decals are being reproduced.
As far as value, the special editions are worth something more than trucks that aren't special editions. At this point, that difference isn't that much. The fact that this truck is a big block is desireable but not 'rare' in its own right. These trucks aren't being collected right now so much as modified and driven, so a nicely modified driver will be worth more to many than a perfect showroom stock truck (though many appreciate those for the blank canvas).
I currently have a Gentleman Jim and an Indy Hauler. My uncle has two Gentleman Jim's and a Beau James. We are guessing that in 10 years or so, they will be more sought after but even then I don't think they'll be big money, just cool to have.
As for production numbers, I've never seen any for these trucks period that I believed. None directly from GM so it's tough to guess at what they might be. Just from what I've seen and people that have contacted me, the Beau James is more rare than the Gentleman Jim.