[KLF] Sample id needed

Hi, I'm looking for the original source that The KLF (and various other remixers of that time) used in the so-called "Primal Megamix", a mix you can find on many ftp servers. The sample itself goes like "Come on y'all, let's rock ya, rock ya" Any clues? It's been pretty famous on acid house records of the late 80s... Cheers, Dan --- a.k.a. Kuta, KLF Online (www.klf.de)