Jim Carrey knew that Ron Howard was trying to empathize with his suffering on the set of

The Grinch the day the director showed up wearing the same claustrophobic, confining latex-and-fur costume. But as the actor explains, Howard's well-intentioned effort fell a tad short.

"It was a cool move of solidarity, but he didn't [wear] the green contact lenses which are really what pushes you over the edge," Carrey tells TV Guide Online. "Once a little artificial snow gets in them, it's all over. Actually, I wanted to make Ron dance around for a while so he'd really understand what I was going through. It was like being buried alive on a daily basis."

Such trauma eventually took its toll on Carrey. In fact, after being encased in the Rick Baker-created Grinch outfit for hours, the Ace Ventura star would lose it. "I'd start to punch myself in the leg," he recalls. "It's like if you give yourself a little extra pain, it takes your focus off how uncomfortable you are.

"Being in that thing was really a lesson in Zen," he adds. "I couldn't even scratch my nose, much less breathe through it. And I had to talk around a set of false teeth which made me sound a little like Sean Connery."

While Carrey is practically unrecognizable as the Mean One, the Golden Globe winner's trademark facial contortions are very much on display. "It was a challenge," he concedes, "but I thought I had mastered it the day people told me that, even wearing contacts, they could see the soul in the Grinch's eyes."

Ironically, Carrey says his Grinch garb actually would come in handy in real life — if only to hide from overzealous fans. "I don't get a lot of freaky people who do weird things," he says. "I get people who just want to love me, but there are times when I don't love myself and I don't want to hear about it.

"Some days, instead of just being the biggest speck in the universe, I want to be the smallest — just a nobody," he sighs. "But that doesn't happen a lot."