Looking at old Wagon Train shows, you can see that he liked to wear tight clothes.
Apparently, he needed to keep his wayward bellybutton tied down with a sturdy, wide leather belt.
Also the star of "The Green Slime". Probably considered Grade Z it's a movie that does what most movies are supposed to do but don't, entertain. It's goofy, the effects are bad, a co-production by the Godzilla studio in Japan and MGM but it's actually fun with the grooviest theme song ever.
And he played Starbuck in 110 IN THE SHADE, the musical version of THE RAINMAKER on Broadway.
Loved him and watched endless boring episodes of Wagon Train as a kid in the hope he might doff his buckskin shirt.
But unlike the evidence in the OP's photo, he rarely, if ever, did.
He had a great masculine square jaw and devastating dimples, a lethal combo. And the perfect 1950s hairstyle, enhanced by Western sideburns.
Any truth in the rumor he never got along with his costar Ward Bond?
Back in those days, men wore their trousers up high and cinched in with a belt, in the smallest part of the waist to show just how small their waistlines were.