Archie Clark - Millport

[BUDERIM ROSS]

G'dday,
I'm trying to get some background on my grandfather Archibald Clark, born Millport 1880, died Millport 1948. He was a merchant seaman and served in the RN in WW1. He is described on his death certificate as a "Cemetery Superintendent", presumably in Millport where he lived.
On my father's (Duncan Clark) marriage certificate Archie is described as a "Ships' Master". I believe that this may relate to times in the 1920's /30's when he was a yacht or inshore vessel skipper, not an ocean or coastal ship master.
Can anybody with a long memory advise or point me in the right direction. (I have tried the usual research avenues, National Archives etc.)

Regards

Ross