"I have never had such a nervous day in my life," Stewart, 60, told KABC-TV, Los Angeles, at his star's unveiling.
His pregnant wife and CNN host Larry King standing nearby, Stewart told the gathered throng he did not have a speech prepared.
"I'm here to wing it like I have my entire life," he said.
The rocker-turned-crooner has been churning out hits for 40 years such as "Maggie May," "Forever Young" and his one try at disco, "Do Ya Think I'm Sexy?"
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