I don't think the pilot's age had anything to do with this. There was at least one guy who was 82 and was an aerobatic instructor. I think that as long as a pilot can pass the physicals and has no sign of demential and such he/she should be allowed to keep on flying. (Personally I think the requirement that dictates airline pilots have to retire at 60 is stupid as well -- from what I remember, the requirement didn't have anything to do with age related problems)
From what that still picture shows (if the shot is legit), it looks similar to what hambleoldboy described.
BTW: Regarding to the statement of racing a P51 at 500 kts at low level... I was under the impression that the P-51 was only capable of those speeds in a dive, though it wouldn't surprise me if it was the case.