Hello "Adam Evans ",
Sorry, my earlier reply with parent names was a reply to "corahlf"
There is nothing showing on online AUSTRALIAN electoral rolls for a "Ieuan" OWEN.
If he did in fact travel on to TASMANIA, you would be better posting on the TASMANIAN message board as TASMANIAN electoral rolls are not available online after 1954; perhaps someone could check the rolls for you.
SOUTH AUSTRALIAN rolls are not available online at all.
Most AUSTRALIAN marriage index closed off in the 1940s - 1960s & most AUSTRALIAN deaths index closed off before or by 1985.