Toughest hombre west of the Pecos?

Actually, Wayne was the toughest man south of the Picket Wire. Wayne would have bashed Clint upside his head with the butt of his Colt. Absolutely no contest. Suprisingly, Clint's the tube guy, with Wayne a very early adaptor of solid state. Despite that, when the smoke clears Lee Marvin is the last man standing.

Both Jack Palance and Burt Lancaster were mentioned. Here's a story about the two of them:

Once, while filming a fight scene with Burt Lancaster, Palance actually punched the unsuspecting Lancaster in the face. Tough guy Lancaster responded by socking Palance in the gut, causing him to vomit.

And Palance was a professional boxer before he became an actor.

The film was "The Professionals". It probably had the all-time toughest homebre cast. Lancaster, Palance, Lee Marvin, Robert Ryan & Woody Strode.