I grew up on the Lower east Side and played skulley throughout the late seventies/early eighties. I just read your rules document, and it seems complete. We had prepainted boards that did not have numbers in the skull except 13 of course. We just gave everyone 6 boxus/advances if you knocked someone out of the skull. If you knocked them from skull section to skull section it was treated as a standard hit. Our start was also much further from box # 1. Usually on the oposite side of the board, so beginers often found themself in the skull on turn one. We often switched caps when we became killers and used blasters. My favorite was the libby caps (about the size of todays snapple caps)