I assume you have this chip marked Joe Wells on the back? As far as I know, the names on the back of this series of T-bird chips are managers/CEOs or the like. According to the unlv casino history page (link below) the owners of the Thunderbird from 1948 to 1976 were: Marion Hicks, Major Riddle, Del Webb Corp and Major Riddle until the switch to Silverbird in 1977.

http://www.library.unlv.edu/arch/casinosbyname.html

Everyone should have this site bookmarked... Chock full of reference info on what was what, when and where, openings, renovations & closings. Check it out if you havent before.