When I posted this in 2012, a helpful reader sent me in right direction to identify "Mark Wolf":
The bearded guy he is with, and later with Paul Barresi in “Encounters in the Woods”, might be MarkWolf or Wolff. I know there is a more contemporary bodybuilder at markwolff.com, but I seem to recall that was this guy’s name as well. I might be wrong. In “Encounters on the Rocks”, the more muscular guy with the shorter hair is Dan Pace aka Rocky Genaro. The twink with Paul Barresi in “Encounters in Black” might be called Chuck Grady.
I looked him up, found some more pics then promptly forgot to do anything with it.
Well after more than a year, here we go. Sorry it took me so long Tom.