Revisiting this and now having access to the Ancestry Library service I have found a pension record where the service number, 36614 matches the one on his grave in NZ. Date & place of residence also match. It shows he was in the East Yorkshire regiment. Further search found he was admitted to the 51st field hospital on 31/3/1918. His number is incorrectly recorded as 36414. I do not have access to the full pension record. Is it worth subscribing to get it? Any comments gratefully appreciated.