The 34-year-old paceman returned the second-best figures by an Australian in a Test innings behind spinner Arthur Mailey's nine for 121 against England in Melbourne in 1920-21.
McGrath picked up the first seven wickets in Pakistan's woeful second-innings total of 72 before fellow seamer Michael Kasprowicz captured the eighth and 10th wickets to record figures of two for four.
"I had seven-for. I was looking up thinking this might be my best chance for a 10-for," McGrath told a news conference.
"But then Kasper came in and ruined it," a grinning McGrath added. "I couldn't be happier at the moment."
McGrath, who took three for 52 in Australia's World Cup final win over India last year, said he was aiming to play in the 2007 tournament.
"The way I felt today I'd definitely like to see myself there (in 2007). We'll have to see what happens," he said.
McGrath missed a year of cricket with a long-term ankle injury, returning in the first Test against Sri Lanka in Darwin in July to claim match figures of seven for 61.
"Towards the end, that's as good as I've ever felt bowling," McGrath said of his eight for 24.
"When I came back, after having so much time out of the game, I just felt fresh and ready to go," he added.
McGrath, Test cricket's fourth leading wicket-taker with 472 victims in 104 matches, surpassed his previous best of eight for 38 against England at Lord's in 1997.
He said he ranked Sunday's performance slightly above the England match, despite what he felt was a patchy start to his spell before taking the first wicket of the day when Pakistan's Salman Butt was caught in the gully for nine.
"It wasn't until Matty (Hayden) took that catch and then things started to turn around," McGrath said.
