94 V6 gauges to GT gauges

The clusters are not the same. Starting in 1996, the speedometer is all electric driven by a signal from the PCM. The 1996+ cluster also has support for the anti-theft (PATS) system.

The 94-95 Model Year is a "in between major change" model years. 94-95 is an early ODB2 set up that does not fully support all of the ODB2 standard. In some regards, it is closer to ODB1. That is why the 94-95 Mustangs are in a forum all by themselves. Because they are different in key areas.

However, there are large subsystems that are shared in common.

I am not positive of all of the differences between 94-96. Best for you to do more research.

Consider getting a service manual for your MY. Review the wiring diagrams.