'The Enforcer' showed good form at last month's Wilson Security Sandown 500 and earned a top 10 finish with Perkins.
The pair battled through the field after starting 24th at the 500, with Perkins caught in an incident with Craig Lowndes in qualifying.
"There's no reason why we can't stand on the podium this weekend," Ingall said.
"We're very confident. With everything that's happened, there's one thing that would put a smile on James' face - to see that #22 on the podium.
"We're not here to mess around and fill a gap. The guys have gone to a lot of trouble to get this far - the preparation of the car - we're going to have a big stab at it.
"There's no reason why we can't stand on the podium this weekend."
Funnily enough, Ingall's two wins in the 1000 came with Jack's father Larry Perkins back in 1995 and '97.
"There's so much history there with Jack Perkins - I look at that vision from '95 and Jack was a little bit higher than my knees and crying when his dad ... both of us won the race," he said.
"Now, there we are sitting in the same car, in the factory Holden Racing Team with the Perkins name and the Ingall name on the side of the car again.
"There's a lot of history and it'd be a movie script story if we did get on the podium. Imagine winning it - it'd be huge!"
So much prestige is attached to the Great Race and with so many variables to face on the day, anything can happen out on track.
Ingall understood how hard it was for Courtney to stand down - but is looking forward to a crack in what he believes will be a very competitive race car.
"Forget the Championship, we still look at Bathurst as the standalone race because of the stature of it," Ingall said.
"The team has worked so hard over the last few years in a big rebuilding phase that's been very public. I found out at Sandown that the cars were very competitive and James would've been a genuine contender to win this race.
"So not to be here is a huge disappointment for the team and for him, and like I said, I know he's trying to put on a brave face but he'd be absolutely fuming inside and very gutted."
Results have been lean for the factory team this season - but a strong performance at Bathurst can transform a year. For Ingall, it's not just about doing a good job for Courtney, but the whole Holden Racing Team.
"We got thrown in the deep end at Sandown, but I sense that it's a very good team, very professional, and has come a long way," Ingall said.
"The car's competitive - we were a top 10 car all Sandown - so it's still looking alright.
"I'm really looking forward to it and the good thing about it is there is no pressure, you come here have a steer, I'm not auditioning for a full time drive - come here, do the job and have a good time and enjoy the weekend."
A bit more notice meant Ingall was able to prepare for what is a long and physical race around Mount Panorama.
"I've been getting into the Skaifey school of wine tasting since I've been doing commentary duties so that had to be banned!" he joked, referring to his fellow FOX SPORTS expert Mark Skaife.
"I was a bit underdone at Sandown but I've been hitting it pretty hard since then and dropped a few 'kgs'... this is one of the toughest circuits in the world, so if you're not fully race fit it'd be a hard ask, so had to do a fair bit behind the scenes and get ready."
Courtney announced to media this morning that he would step back for the weekend, with a chance of returning for the Castrol Gold Coast later this month.
While disappointed not to be in the car, the 2010 Champion was pleased to be back in the team environment and with Ingall doing the job on Sunday.
"He's done a few laps around here!" Courtney said of Ingall.
"He did a great job at Sandown - 'the Muscle' is a good mate and of anyone I could've picked it's good that he stepped up.
"I'm pumped, I don't how happy I'll be if he wins the thing on Sunday, but it'll be good."