"It's like a party in my mouth..." origin

Factual Questions
1

Does anyone know the origin of the phrase “It’s like a party in my mouth, and everyone’s invited”?

I know that there are two Simpsons episodes that use the line, and a Futurama episode that uses a variation of it.

Did this originate from The Simpsons? Or was there a commercial or some other previous origin?

2

There was an ongoing skit on SNL in the 80s about a party in my pants and you’re all invited.

3

This website dates the first print version as a Popeye’s Chicken ad, but I swear I remember it as an R-rated grade school taunt (which would have been around 10 years before '82):

"It’s like a party in your mouth…

…and everyone’s coming!"