Hansen has told the squad the probable selection, and has stated that the starting line-up will be announced on Friday.
"There is probably only one position I'm still tinkering with in my mind, the rest I'm pretty sure of," said Hansen. "We just need to tighten a few nuts here, screw in a few screws and make sure that we are ready."
The squad have been in Australia since early last week, and preparations for the championship are in full swing.
"We need to be ready with our set pieces and ready with our game plan, and that people understand what their roles are as individuals and as a collective group," said Hansen.
Wales' first game kicks off at 9 am (UK time) on Sunday.