Thanks for all the comments - as we dig more into our GMC, we're appreciating more the uniqueness, but everything is in pretty rough shape. We are trying to salvage what we can and preserve it well, right down to not using new tail light lenses because they have a bow tie on the lens. Our body shop has pretty much talked us in to faux patina, so we can preserve rare parts like the hood.
We're starting up a blog to track the progress of the build:
http://1966gmcratrod.blogspot.com