LOL, I guess technically ZZ Top’s “Manic Mechanic” is a rap song......That’s Right!
I had Deguello on cassette, Manic Mechanic is definitely an oddball tune. I think Blondie's "Rapture" was on the radio at around the same time, so there might've been some spoken-lyric influence going around. At the time, it just felt like a novelty tune... a bit later in the '70s than most.