Congrats Bob!
Dieter Marshalls book has a small chapter on these. I am out of town (for a long time), but his book has the most information on these rare puppies.
abe books has one of his copies;
WALTHER PISTOLS: MODELS 1 THROUGH P99, FACTORY VARIATIONS & COPIES
Dieter H. Marschall
http://www.abebooks.com/servlet/Book...lther%26x%3D85
also on gun show books;
http://www.gunshowbooks.com/cgi-bin/...05&sid=6J7890s
ed