The Shakespeare Mummers have been singing "Not for Joe" including a variant of that verse at the end of our plays for many years:

My Uncle Billy had a ten foot willy
And he showed it to the girl next door.
She though it was a snake, so she hit it with a rake
And now it's only five foot four

We've never changed that verse, but we did change the first verse:

We had a little N***** and he grew no bigger
So we put him in the Wild West Show
He fell through the window and broke his little finger
And he couldn't play the old banjo

This is now
We had a little mummer and he was no strummer etc