Local fire officials said the worker was doing maintenance on the sign, located at 24225 Lorenzo Road in Wilmington, about 11 a.m., when the lift he used to get inside had an issue.
The sign is roughly 130-feet tall.
There is no ladder inside, fire officials said.
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Chopper 7 was over the scene about 3:30 p.m.
There was a huge police response, and a crane was seen being brought in.
The man could be seen inside the sign.
Just before 4 p.m., the man was seen getting into the crane basket and slowly brought down to the ground.
He was then placed into a Wilmington Fire Department ambulance.