Guess I've heard of it so I Googled "prison casino" and came up with this pic! the caption reads: Below is a 1963 photo of Joe Conforte taken in the Nevada State Penitentiary's prison casino. Chips!

Guess I've run across this site before... sheesh, the stuff online. Sheesh, the places I end up online! Got a history on Joe and the Mustang Ranch, work to it from this page at your own risk: http://www.davesworld81.com/mustang_killing_2.htm

I scanned the Google list but wasn't able to find anything else useful.