The service document I use for the 94 was a Haynes document supplied by the dealer when the car was purchased in '96 and is similar to most I have seen of that type. It covers up through 95. I have not given much thought to what other variations are and have limited exposure to them. Although a friend of my had a 99 which I maintained for him and I don't remember getting into trouble using the documentation I have. As close as I remember the differences were mostly cosmetic and with body work. The only other was a coupe similar to the one I own, but I don't remember the year.

yeah i have a 95 and 97 sc2 and I routinely use the 91-93 book for them with no issues.