Bob Hunt was able to identify two of those three pilots from that 71 Team Trials. Of the 23 people that were there, I can recognize most of them except for the three in these photos. From those already identified, then the one in that first photo could be:
Steve Johnston
Donald Buffo
Neal Thompson
R.G. Tran
Bernie Trent was there so that piece of information by Bob is probably good.
To respond to Chris, yes, Dave Gierke was there as a judge. He also wrote a good article on that 71 stunt team selection finals in the Jan 72 issue of Flying Models.
Keith