In a recent interview with Peter/Kendo, he pointed out that the Kamikaze Crash was never quite as devastating as it looked, and that he himself was more at risk of getting hurt than the wrestler on the receiving end!
I've always thought that the splash, whether delivered by Daddy or Stax, was never a particularly dangerous move, but that both Martin's elbow drop (which he seemed to prefer later on in his career) and Shirley's double elbow back drop (as practiced on John Quinn at Wembley and Tony Walsh countless times elsewhere!) had the capacity to cause some damage if not done carefully.
The reverse surf board was a favorite finishing move for George Kidd, in his early days.
That may have been before he discovered the "roll up in a ball " pin fall.