Just found this on Tumblr posted by Vintage Las Vegas.

The Landmark, 1969. View from the Skybar at the top of the hotel in the year they opened, Paradise Rd & Convention Center Dr.

Original thumbnail is in place still.

The person in the photo might look like Stupak and maybe it is, but unsure. Looks like the Skybar did have slanted windows at the top. The one or two stories below had straight windows.

Thanks for pointing that out Mike. Wish there were more photos out there, but the selection is slim.