Friday Flashback: I was recently reminded how much I enjoy looking at Mark Brandon — a classic centerfold model & part-time gay-for-pay porn actor from the nude skin mag era. He certainly had everything in the looks department. Cute face, athletic build, luscious round bubble butt and an absolutely perfect cock. Good girth, nice length and a plump mushroom cap. Savor a slice of this beefcake as he lounges by the hot tub with a hard-on in this vintage nude photo shoot after the jump…