It appears that Michael Fleisher modeled the story of Jonah's death, published in 1978, on this story from 1977. In addition to this, Secret Origins #21 had the secret origin of Jonah Hex and in that story a B-movie is being shot in an amusement park, a woman stumbles and falls against the 'statue' of Hex and then they discover that a real body is inside. Does that sound like this....
One day, while filming a TV episode of The Six Million Dollar Man at the amusement park, a workman moved McCurdy and his arm fell off, exposing the skeleton within. The mysterious dead man was autopsied by the LA County Coroner and made the headlines. People wanted to know who the body belonged to.
Oklahoma eventually proved that it belonged to Elmer McCurdy, and in 1977 he was finally given a proper burial in Guthrie's Summit View Cemetery next to Bill Doolin, another outlaw. The cemetery refers to these two graves as its "Boot Hill."
I don't know if anyone ever asked Fleisher what was his inspiration for The Last Bounty Hunter, but I think we have our answer.