Here, Rod, this link is a little more comprehensive in its explorations. Not because it's
my link, it just is...actually I was hoping Dr. Bill's link opened a few more doors...I just want more information! It seems we have an insolvable phrase origin! This links gives references going back to the 1800's. But, as everywhere, no source is uncovered.
Here is a fascinating and thorough discussion on the possible origins of the phrase
"the full monty", an excerpt from the newsletter of the Quote/Unquote site I mentioned a little while back...here's the URL:
http://www1.btwebworld.com/quote-unquote/p0000029.htm