Good article on Zimmerit about Expo 70 in Osaka. There's a connection to Tsuburaya inside that huge monstrosity: http://www.zimmerit.moe/expo-70-osaka-gainax-patlabor/
Visited Banpaku with Hossy from Pop Soda (Twice, although the first time was on a Wednesday and it was closed.). There is an AMAZING museum there and a few of the buildings still stand. Many tell me as kids their parents took them and there and it was incredibly hot weather, and a few hour long waits to get into some of the exhibits. One person told me that was the first place they ever saw a westerner. There was also a now-closed amusement Park nearby that a daytime full-park-capacity roller coaster decapitation occurred. Cool place. Recommended.