True story. Back in the late sixties there was group of girls that followed the rock stars around and made plaster casts of their penises. There was an article about it in one of what we used to call the "underground" newspapers. They claimed they had done Hendrix, Clapton, Jagger and a bunch of others. I seem to recall they had photos too.
Plaster Casters
http://www.cynthiaplastercaster.com/