This is the version in Heinz Pagels, The Dreams of Reason (p. 266); he says he got it from Sydney Brenner:
Crick, the co-discovered of the molecular structure of DNA, dies and goes to heaven. He is met by St. Peter, who asks if he has any special requests. ``Yes,'' says Crick, I want to meet the Man himself and ask him a few questions.'' Peter says that there are not many requests of that kind, but it can be arranged, and he tells Crick to follow him. After passing through the Elysian fields, with their cool springs and lakes around which beautiful people are at play, their every desire fulfilled, Peter and Crick come to the mountains and enter a dark valley. The way is strewn with wrecked machines, electronic parts, broken glass and test tubes, organic garbage, old computers ---- a junkyard. At the end of the valley is a shack, which they enter, and inside is an old man, his coveralls stained in grease, blood, and chemicals. He is bending over a lab table filled with more junk, hard at work. ``Francis, meet God; God, meet Francis,'' says Saint Peter. ``Pleased to meet you,'' says Crick,``but what I want to know is how you made the muscle system for the fly's wing. It's so ingenious.'' ``Well,'' says God, ``I did it a long time ago, and it's really very simple. Let's see now if I remember. You just take a bit of tissue and then it's...well, twisted..and then, somehow...and then you rearrange...slap together these protein chains...and...Well, I don't remember all the details. But who cares, it works, doesn't it?''