Ian:
Congrats on the find! I am just south of Seattle, and have a friend Roy, who had Seattle Packard (the restoration shop, not the dealership) for several years. We are getting together this weekend to take my 47 Clipper to show up the RR owners club, I'll print your pic and info and see if he knows anything about the car. He's an amazing source of info on things Packard in the Seattle area. See: "At the State Capitol" in recent photos for my Custom Super Eigth. I think a guy by tne name of David Moe has bought out the inventory that Roy had,and is using Packard Seattle, or something like that as a website, I'll see if I can found out more about that for you, too
Good luck--love to hear those 12's purr.