Jim O'Heir mistakenly wore Nick Offerman's tight outfit on “Parks and Rec” to avoid being a 'troublemaker'

"A rational person would've taken it off and brought it to the attention of the wardrobe department," O'Heir jokes. "But not me."

Jim O'Heir just wants to play by the rules.

In his new book Welcome to Pawnee: Stories of Friendship, Waffles, and Parks and Recreation, the star of the hit NBC sitcom Parks and Recreation recounts a hilarious example of where his fear of being branded a "troublemaker" has landed him.

"Once, I arrived at my dressing room to find a pair of khakis and a red polo waiting for me," O'Heir recalled of a mid-series Parks wardrobe test. "I changed into them but noticed that the shirt was small. I mean comically small. A rational person would've taken it off and brought it to the attention of the wardrobe department. But not me. I wasn't going to be a troublemaker, and if they thought that's what I should wear, then dammit, that's what I'm going to wear. And so I did."

Related: 15 things we learned about Parks and Recreation from Jim O'Heir's Welcome to Pawnee memoir

O'Heir continues: "Later I ran into [costume designer Kirston Leigh Mann], and she asked me how everything felt. I sucked in my stomach and said, 'A little tight, not gonna lie.' 'I'm not surprised,' she said. 'That's [Nick Offerman's] outfit.' There was a wardrobe mix-up and his outfit landed in my dressing room. By the time I pointed out the ill fit to Kirston, I'd already shot a scene in the clothing... We had a big laugh about that one."

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O'Heir is able to laugh off the mishap now. He even points to the episode where the flub made it to the final cut, if you want to watch it for yourself - the season 2 episode "The Camel." But as a larger-bodied professional in an industry that overwhelmingly caters to smaller bodies, he's also honest about the unfair challenges and disappointments he's had to face over the course of his career.

"To this day, I don't enjoy wardrobe fittings," he says. "I convince myself the designer is judging me the second I walk in for being a bigger dude, even if, in reality, there's no judgment coming from anybody except myself. It's the fear that, for the next hour or two, I'm going to be exposed and vulnerable in front of a stranger. You know that feeling of dancing for the first time at a middle school end-of-year party, where the lights are barely turned low and you don’t know what the hell you’re doing and you’re sure that everyone is watching? When slow dancing meant putting your heads on each other’s shoulders?I feel that same awkwardness in wardrobe fittings, the difference being that the lights are turned on very bright."

The actor behind everybody's favorite love-to-hate Parks character, Jerry Gergich, says he's "done hundreds of wardrobe fittings over the years, and each one gives me anxiety."

"You see," he explains, "stars like [Amy Poehler] and [Rashida Jones] have earned the confidence to refuse an outfit if it's not to their liking. They say no by virtue of being the stars of the show. In my case, the desire to get out of there as quickly as possible often motivates me to say yes."

Related: Jim O'Heir says William Shatner treated him with 'disgust' during Boston Legal guest spot where he was in drag

O'Heir was doubly hemmed in, so to speak, by the fact that wardrobe departments are often unprepared for actors with his body type, and by his ranking as a recurring character on Parks, not a series lead like Poehler or Jones.

But O'Heir has only positive things to say about his experience working on Parks for seven seasons. In a conversation with Chris Pratt in Welcome to Pawnee, he tells his former Parks costar, "You checked in on me, Amy checked in on me, and it’s not like I expected everyone to check in on me," but the fact that series leads with more power and influence made sure he was doing okay "meant the world to me."

Welcome to Pawnee: Stories of Friendship, Waffles, and Parks and Recreation is out now.