Aftermarket gauges back to factory gauges questions.

[Jayschevy]

When I got my truck the PO was using aftermarket volt, water and oil gauges instead of the factory gauges in the instrument cluster. I'm not sure if the old cluster worked or not but since buying the truck I bought another cluster but the water and volt gauges still do not work. My question is:
1. On my trucks factory volt gauge in my cluster can I just unhook the 2 wires connected on my aftermarket gauge and just hook them up to the two connection terminals on my factory gauge to get it to work?

2. Just hook up the fitting on my aftermarket oil pressure gauge to the factory oil pressure gauge to get it to work.

3. How do I get my factory water temperature gauge to work? My factory water temperature gauge only has electrical connections in the back. My aftermarket water temperature gauge has some type of probe going to it. So how do I remove this to get my factory gauge to work?

Any help would be appreciated.