Here's a Chassis wiring diagram for a 2002 Windsor.
When you open it you will have to zoom in ~+800%, it will be BLURRY, Hit CTRL5 and it will clear right up.
Use the search function to find the Speedo.
There are 3 wires connected to it based on the diagram. One wire is from the IGN, one is GND, and the third comes from the VSS which is the interface between the chassis and ECM. Not sure on the reset unless it goes to ground, you might have to check with the gauge manufacturer on how it resets.
Look closely at the wires, almost all of my wiring has a label printed on it, you should be able to distinguish which is which.
All the Dash gauges share a ground, Monaco usually daisy chained the grounds.
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