Went to Zipollo a few years back. Got quite a few GT's but nothing over 15 Kg. Very different terrain - got a lot of my fish in inland waterways casting over bommies - to the Coral Sea , etc.
Actually had the most fun fishing light tackle of the jetty at Zipollo - got GT's , Bluefin , Silver Trevally , one type of Trevally that we had to get an ID chart out for , Long Toms, Queenfish, Barracouta, mangrove jack (at night ) , various sharks , etc.