A proud McCarthy struggled to put Wolves' success into words and insisted their promotion had still not sunk in - while they are also within touching distance of the Championship title.
But having failed to save Sunderland from a bottom-of-the-table finishes in 2003 and 2006, he stressed he does have a point to prove among the big boys.
"Of course I do, given a sporting chance," said the Wanderers boss.
"If I'm given £6million to spend like I was last time, which included transfer fees, wages, signing on fees and agents fees then we'll all be in trouble.
"But of course that won't be the case.
"Last time I think I had a bit of naivety, I also think I had the usual 'well, if that's what I've got then I'll do it' arrogance to think I could.
"We didn't get bashed up, we didn't get a lot of points, but I didn't really get a chance."
The script was written for Sylvan Ebanks-Blake to grab the goal that settled matters on an afternoon full of emotion - his 25th of the season, one more than the tally that won him the Championship's golden boot award last term.
The industrious Andy Keogh, who has emerged from zero to hero in eyes of the club's fans, harried and hassled Damion Stewart in the penalty area as he looked to shepherd the ball to safety just a minute after the restart.
And when he nicked in to grab the ball by the byline, Ebanks-Blake was in plenty of space 12 yards out to fire home and send the Molineux crowd wild.
"I'm not sure I can articulate well enough how I'm feeling," added McCarthy.
"I'm knackered, I'm beaming on the inside, I'm absolutely thrilled by our achievements. "I'm very proud of the players, they've been brilliant all season long.
"It doesn't register, it doesn't sink in. It's not something you can really savour, you just enjoy the high of it for the moment and savour it when I wake up tomorrow."
Overwhelmed chairman Steve Morgan, a born and bred Liverpool fan, admitted the triumph means more to him than Liverpool's dramatic 2005 Champions League victory over AC Milan in Istanbul.
And he jokingly targeted six points from Rafael Benitez's men next season.
"I'm almost speechless, it was fabulous, the culmination of a really hard
season," he added.
"Big tribute to Mick, the background team, everyone behind the scenes, (chief executive) Jez (Moxey) and the players - the players have been fabulous all throughout the season.
"I'm so proud of Wolves and for the city."
QPR caretaker manager Gareth Ainsworth, who only took the reins from Paulo Sousa last week, was gracious after his side's defeat ended any faint mathematical hopes they had of making the play-offs.
Rangers put up a brave fight throughout, restricting the hosts to a limited number of clear-cut chances.
And they could have spoilt the promotion party in the second half had Rowan Vine's deflected effort not come back off the crossbar or Heidar Helguson taken his chance when put clean through.
"I don't want to take anything away from Wolves, it's their day," said Ainsworth in a brief post-match appearance.
"I've got a lot of respect for Mick McCarthy.
"It would be nice to be in the same situation next season"
He added: "I think this was one of their tougher games.
"We could have put a dampner on the situation had we taken one of our chances in the second half."