Torrey,

The Mason hub records for the WHC says.
Wm H. Clark
1631 Alamitos Ave
Long Beach, CA
400 chips - 1940

At the bottom of the card the name is written out as "WILLIAM."

TGT entry that says Wilbur Clark pre-dates the Mason and TR King records being available to the authors.
It shows that attribution by Doug Saito to Wilbur Clark. Maybe you should ask him where it came from.

I'm told:
Wilbur lived in San Diego before moving to Vegas in 1944.
These chips were delivered 100 miles away.

IMO TGT entry needs to be changed to fit the actual facts.
Sorry.