I was the duty "Crab" on exchange to 651 Sqn from 73 -77 - and most enjoyable it was too!
Just had a look through my logbook for some tail numbers: XW 796, XP 897, XV 136 and XV 129 were 651's Op Banner cabs at Omagh this time in 1974. How time flies!
Paco, I think I've guessed who you are. All the best.