Many thanks for all your replies. I persevered with Googling after I'd posted and found, firstly, that I was wrong about the Martlet and that it is indeed a Hellcat as you say, and secondly that the Sea Fury has been undergoing restoration over quite a long period of time.
I visited the FAA Museum with my grandson a couple of years ago - little did I realise that the Hellcat was the one I'd helped with all those years ago! It's pleasing to know they've both survived and have a secure future.
The memories are rather dim, David - it's 45 years ago now and a lot of water has flowed under the bridge
As I said, I'm not sure whether it was '67 or '68, but I've since found a photograph of XV653 as gate guard on 10th June 1968 here:
Aircraft VX653 (1949 Hawker Sea Fury FB.11 C/N Not found VX653) Photo by Peter Nicholson (Photo ID: AC831372)
Whether the Seahawk was used before or after the Sea Fury, I cannot say. My only other memories of the week were of HMS Eagle cruising offshore in the Moray Firth, re-victualling and taking on a squadron of Buccaneers from Lossie and a visiting Lightning taking off in a rather flamboyant, vertical fashion..........