Looks like a real nice old bike. I wonder if the Classic & Vintage forum would be helpful as well, or perhaps more-so than this tandem area.

The most overarching thought that came to mind as I read your blog was, what is your objective in restoring? That may steer an awful lot of answers to many of your questions. For example, it might be "faithful to the original" restoration, achieving the best performance that the original (or appropriate period) components can achieve. Or it might be, "I want to be able to ride this bike XXX miles in a day over XXX kind of terrain with XXX stoking, and don't really care whether the bike ends up being faithful to the original equipment or period, or a mix+match with modern stuff that works." Whatever you settle on for the objective, establishing a budget up front will help a lot -- avoid the situation where you're 1/2 way done and have reached the limit of resources you want to put into it.

I know I'm not directly addressing the details, for which I apologiz(s)e but I don't have a lot of knowledge to share in that regard. Best of luck with it, hope you get many happy miles on it.