The 25-year-old fly-half has fought back from a series of career-threatening injuries to clinch a late call-up from Sir Clive Woodward.
Wilkinson has not played international rugby since kicking the winning points against Australia in the World Cup final 18 months ago, but has made a comeback for his club side Newcastle Falcons to earn his place in the touring party.
"It would rank right at the top alongside winning the World Cup," Wilkinson said.
But Wilkinson, who admitted he had some reservations about being a late addition to the squad, is certainly not banking on being an automatic choice for the Test team.
He added: "That remains to be seen. I can't really have any preconceived ideas about who is where.
"It's about going out and helping the squad the best I can. Everyone has a huge part to play out there whether or not they play in the Tests.
"If I'm not good enough to be in the team I'm sure I won't be picked."
But he added: "Physically I'm fit and I'm working hard. I'm enthusiastic and ready to get out there."