Meehan is the son of former Australian heavyweight champion Kali.
The 21-year-old won the Australian super heavyweight title at 17. But his NRL career is on hold after he was sacked by Sydney Roosters due to off field issues amid claims from Willis himself that he worked as a standover man.
Dual international, Roosters premiership winner and two-time Rugby World Cup winner Williams is in Gallen's sights.
But Williams is currently out of action for another six months after injuring his Achilles playing Sevens Rugby at the Rio Olympics.
"I have said openly I want to fight Sonny Bill, unfortunately we haven't heard the same thing back so I don't know if he wants to," Gallen said.
"I understand he is injured at the moment and there is not much we can do about that.
"We were looking at February next year. It might happen later next year.
"I have said it before and I will say it again I want to fight him.
"I wouldn't say he is running scared. I know he is injured but hopefully one day it will happen."
Gallen will fight at Star City on December 8 and then back up for another bout at Cronulla's home ground Southern Cross Group Stadium on December 23.
"I start training today and I am looking forward to it," Gallen said, three weeks after Cronulla's grand final win over Melbourne.
"I am used to playing footy in week-in-week-out so I should be right.
"Fingers crossed I don't get too hurt in the first fight so I am right for the second one."