The Manx Missile, who was given a knighthood by King Charles III this month, has 34 Tour stage wins over his career, the same as Merckx.
The 39-year-old failed in a similar bid in 2023 when a high speed crash left him crying and stricken on the tarmac, such is the destiny of sprinters, he said at the time.
"I believe I'm in better shape this year than I was last year," Cavendish said in Florence on the eve of Saturday's departure.
"I wouldn't be here if I didn't think I could do it."
The ageing British sprinter is back at the Tour as the subject of his own Netflix documentary on his personal quest for one last stage win before riding off into the sunset.
But the prickly former Sky and Quick Step speed king has proven he can come back from most anything, including the energy and morale sapping Epstein-Barr virus.
Merckx won his 34th Tour stage in 1975, a record Cavendish matched in 2021.
"When the opportunity comes, you try and make more history," said Cavendish.
"Here, I'm just trying to win more. Look, I don't have anything to lose, and realistically, there are five or six chances for that extra win.
"I know the work that goes into being at the highest level. I'm a realistic person and we go in with a plan and will set that in motion."
Cavendish signed with Team Astana two years ago and this year they recruited Denmark's Michael Morkov and Italian Davide Ballerini to launch their sprint legend into his high speed last-gasp dashes for the line.
"I couldn't ask for more than that," said Cavendish. "It means I don't have any excuses if I don't win."
"The thing I'm most proud of is the length of my career," said Cavendish, who started with T-Mobile in 2006.
"The longer it is the more ups and downs you have, and fortunately I have had, mostly, geat support."
Cavendish went on to say how happy he was that this Tour was starting near his old home.
"I love this sport and always have, especially this race. It's beautiful to start in Florence, I lived here ten years, it's perfect in an emotional level.
Cavendish overcame many obstacles and was teamless in 2021 before his old mentor Patrick Lefevere gave him a chance.
He would win four Tour de France stages that year to level Merckx.
"I'm so happy I carried on," said Cavendish, visibly moved.
The pair are back for one last time for what Cavendish described as "five or six possible chances".
"Everybody would love to see Mark win a 35th stage, but just don't expect us to give him one," said defending green jersey Mads Pedersen.
