If it's an 8v, then it'll be as simple as having an o2 sensor socket, a ratchet, and an extension. If it's a 16v (I don't believe 94 came with them) there's one behind the catalytic convert as well as the one in the exhaust manifold.
No, no, no, no, no! The 16 valve started in 92, and still had only ONE O2 sensor through 95. It may have gotten two O2 sensors after 95, on the OBDII models.
I just used a big box-end wrench to remove all of mine, and never had a problem.

Oh, and it's a lot easier to remove the O2 sensor with the exhaust manifold out of the vehicle. Perfect time to put on that Calmini header - it REALLY makes a difference!