American multiplayer

Playing a competitive-ish game, in which i am America. I will be playing alongside a Britain, France, Prussia, Austria, Russia, Sweden, and Japan. I mainly wished to asked the ideal companies to acquire a large GDP and economic advantage over my rivals, focusing mostly on trade bloc in Americas. I was aiming for Lee Wilson and Carnegie, but i’m questioning the others. Was thing maybe Colt, Generic Furniture/glass, and potentially a tool company? Any advice for GDP maxxing America?