I have noticed there are two different opening credit scenes where the theme song is played with Fred grabbing newspaper and siting down in front of his store, and Lamont driving the truck coming down the street.

In opening scenes from season 1 thru 4 Fred sit down in the chair, and Lamont comes down what it seem like a three way stop where he almost stick out his head.

But in season 5 thru 6, the Fred scene is the same. But when Lamont comes up the street, he makes a right turn and goes down the street.

It seem they reshoot part of Lamont's opening sequences with the truck for season 5 and 6 as he looks a bit older as compare with his opening scene in earlier seasons.

http://pics.imcdb.org/0pb/f100__00_23.jpg