Great catch! And using one of my favorite comedy sketches, too -- though I should note that the Ben Franklin character actually reads the phrase as "purfuit of happineff". (To this concern, Tom Jefferson replies that, "No, it's stylish. It's in, it's very in.") I haven't looked closely at a picture of the Declaration of Indpendence in years, but searching a few online images just now indicates that the typography actually suggests "pursuit of Happinefs" to modern eyes.

"Surly to bed and surly to rise..."

-MTD/neb