Dave B - That aircraft was infact G-AZDC 61424 which was purchased as a wreck from Elivie (formerly I-EVMA) and rebuilt at Redhill. That was the first BHL S61 in the UK and was purchased around May 1971.
G-AZRF 61473 was the third for BHL in the UK, formerly PK-HBT operating in Natuna Besar and arrived around April/May 1972.
The second was G-AZNE 61467, which was later lost after buzzing round the North Sea for a few hours before it sank.
There were pics of G-AZDC and the floor trenches on SkyWeaver, perhaps Tail-Take-Off can stick them up here?