The vertion I heard many years ago-

If ever you see a hearse pass by
Remember that some day you are bound to die

Ho Ho Ha Ha Hee Hee Hee Hee
How happy we will be

They wrap you up in a wooden shirt
Cover you over with lumps of dirt

Ho Ho etc

The worms crawl in the worms crawl out
They crawl in thin and they crawl out stout

Ho Ho etc

Your eyes fall in your teeth fall out
your brains come trickling down you snout

Ho Ho etc