This is the version I memorised some 40 years ago, but it's still clear, so here it is:

Two boys were approached to act in a school play, but each refused, saying that they were far too nervous to act on stage. The teacher told them they would each have only one line and with a month to practice they should have no trouble at all. So the boys finally agreed and were given their lines.

The first boy's line was "Oh fair maiden, I have come to snatch a kiss and fill you soul with hope"

The second boy was told that when he heard a gun fired, he was to say; "Hark! I hear a pistol shot".

Then every day the nervous boys recited their lines and on the day of the play, the first boy stepped forward on que and said "Oh fair maiden, I have come to kiss your snatch and fill you hole with soap"…On hearing this the already nervous other kid blurted out; "Hark! I hear a shishtol pot, pit shot shit pot, cow shit…Oh bullshit! I didn't want to be in this bloody play in the first place."

Not a bad memory for an old fart of 58 eh?