Hi Ken,
Remember me from j-aircraft dot com about 7 or 8 years ago?
If you don't get any hits here on your questions, try this:
http://forum.axishistory.com/viewforum.php?f=65
This sub-forum is very active and has at least three Japanese historians who are fluent in both languages and live in Japan. I have always been impressed with the detailed replies they are able to come up with using obscure Japanese language sources. It's worth a try.
Best,
Larry