To find it, you'll need to:
1. Remove the center console: This involves removing the trim pieces around the gear shift lever. Consult a repair manual specific to your 1994 Grand Prix for detailed instructions on this process. This is usually necessary to access the cable.
2. Trace the cable: Once the console is removed, you should see the cable(s) connected to the gear shift lever. They'll run down toward the transmission tunnel.
Be aware that accessing the cable often requires significant disassembly. If you're not comfortable with automotive repair, it's best to consult a mechanic or use a repair manual.