The 34-year-old beat Malaysia’s Nafiizwan Adnan 11-6, 12-10, 11-4 in Sunday morning’s last-four clash to set up a meeting with New Zealander Paul Coll on Monday.
“To be in the finals for the third time is so thrilling, what an occasion to have ahead of you, it’s tremendous,” Willstrop said.
“I love playing big occasions, it’s really fulfilling.
“The longevity thing is so pleasing and my physiotherapist, Alison Rose, in Leeds has just been an absolute wonder-woman for me all my life, she’s kept me strong after my surgery and thanks to her I’ve been able to play squash until 34 years old.
“Paul Coll is favourite for the final tomorrow and he is an incredibly tough player and has an unbelievable physicality. He has beaten me the last times so if there is not too much pressure, I still hope I can rely on my experience.”
Willstrop, a former world number one, already has four Commonwealth medals to his name, including a silver at the 2014 Games in Glasgow, but is yet to strike gold.
Having seen off Pakistan’s Farhan Zaman (3-0) and Campbell Grayson of New Zealand (3-1) in the early rounds Down Under, the Team England star overcame Australian Cameron Pilley 3-2 at the quarter-final stage.
Monday’s gold medal match will get underway at 10.30am UK time.