I thought, "He's trying to pull a fast one".
or
I said, "I've been on telly but I'm no Dean Martin".
or
The bartender offers him a warm smile and says, "For you, no charge".
or
Two. One to change the bulb, and one to write a song about how good the old light bulb was.
or
Five: one to handle the bulb and four to contemplate how David Sanborn would've done it.
or
A blackboard.
or