The vets who deployed with the Ferrets in the 60s are now old men. But, they have children and grandchildren. There is also a network of regimental associations, such as the Guild of the RCDs. In my experience, the associations have a good sense of who is still around. Present your question to the Guild and you might get lucky.
Secondly, if Ed or Collin have operational records, are they any names? Even a CO, Ops O, or Ops Clerk's name is a start. You might enlist their help to reconnect the vehicle with the crewmembers.
Finally, I just want to say I'm pleased that you are getting so much enjoyment from your Ferret. See the note below from the British government. (((
https://www.gov.uk/guidance/coronavi...th-coronavirus ))) This advice includes not sharing food, kissing or cuddling your ferret.