Unfortunately I don't know since the SCO machine was burnt to a crisp in a fire. The company that sold it originally has been less than helpful (I also think they don't know what they sold), therefore my problem.
Someone mentioned that with SCO 5 most likely it would have been a tar backup. I have tried reading this tape with CA and Veritas products without success. I know I need some utility that will dump the tape out and then maybe I can re-construct it (yeah, I know, lots of luck there too)... but at least is a chance.