Nice find
. My two cents, I'd sign on with Ross in that Bob's answer is the most comprehensive. For me, I don't think I could go through all of that with any level of patience though.
I would definitely index the distributor, pull it, pre-oil, use a breaker bar to give it a half turn, oil again and then drop it back in just as it was. You'd also probably need to find a way to get fresh fuel to the carb as soon as possible too. I have seen 40 year old gasoline and you don't want to draw that thru the lines and into the carb. A stand alone supply and a line to the pump could be a good idea.
Maybe pull the plugs and give it a dash of the marvel mystery oil treatment, crank it over a couple rotations with the plugs out, stick 'em back in and then fire it up.
Ultimately, as stated gaskets and seals will definitely need replaced, so it is gonna have to come apart some, but hearing it run with or without strange noises will give you confidence on what you're dealing with before you start.
Like Jay said, pictures would be nice too.