The censored parts of the lyrics should be commonly known among people who know the song. Naturally, these parts are also missing in the regular video clip. But in addition to that, the picture material has also been modified slightly. More or less, this is rather a report for completists.

The uncensored version of the clip can be found on the Jay and Silent Bob Strike Back DVD. (A thank you goes to Snake Plissken for providing the information)

Beginning 2. Min
This scene is more or less commonly known and not really spectaclar.
In the lyrics:

"I was gonna eat your pussy too but then I got high,
now I`m jerking off and I know why, because I got high, because I got high“

the two swear words (marked in bold) have been removed from the audio track.
In addition to that, an alternative shot of Afroman was inserted, for the scene, where he uses the second swear word "jerking". In this alternative shot he is is just grooving along, this was probably done to avoid complaints from lip-reading viewers. The uncensored version shows him siting on his chair singing the full line.

To modify the scene where he sings "pussy" was not necessary, because this swear word was sung in the off.
No running time difference

Uncensored:

Censored version: