I saw a video on YouTube in which a modeler used Lego ball joints for his Imai/Bandai Monster kit. Somebody sent me a link to that video and the result looks great. (I think it could have been the builder himself, but I can't remember.) I cannot recall the name of the channel, but maybe you can find the video through a search. I'm also finding that Japanese model builders can provide a lot of great information too on modifying these older kits to really make them look much better, less stiff and more stylized. Your work on that Gerwalk is fantastic