Except the RAF ordered the mk 2s before RN ordered the mk 5, and the mk 2 preceeded the mk 5 into service
OK
Davef68 -it's a fair cop.
But preceded only by a few months, Mk2s in Feb '64, Mk5s in Jun/Jul '64, so I guess pre-production examples were flying at the same time.
And it's a shame to spoil a good story with facts!