Good evening Mel,
I'm pretty certain that I have identified the challenge aircraft as one first flown n 1962!
However, and I hope you don't mind, as I have to attend an open ended family gathering this evening, I'm reluctant to declare another open house and so I will withhold my answer in the hope that someone else will be able to join the dots to provide the answer (and put up another challenge)
I'l check in when the party's over and see what's happened!
