installing gauges, need help/advice wiring oil temp and pressure gauges Options

[914 RZ-1]

I got oil pressure and oil temp gauges. The instructions are generic and I'd like some specifics about how to install them on my 1.7L '72. Sorry if these seem obvious; I've never done this before.

1. Standard ground or floating ground? I'm leaning toward floating because it looks obvious how to attach the ground. On the standard ground, how do I attach the gnd wires?

2. What do I attach the wire from the gauge light socket to the light switch to? The headlight switch? Which connector?

3. Which fuse do I use for power? #9?

4. I figure I will just attach grounds to a screw on the body, either an existing one or a new one.

5. What is the "switched +12v" light shown in the instructions? The dummy light?

6. Does the oil pressure sensor get installed where the current oil pressure switch is by the distributor? Doesn't appear to be any room, but I'll need to move some hoses, etc out of the way.

7. Where does the oil temp sensor go? The instructions state that it can replace the drain plug. Is this correct?

8. Where is the best route for the wires? I was thinking thru the middle along where the other wiring harness is located. What should I do with them in the engine compartment: zip tie them to other wires, or let them hang free, or what?

If anyone has done this and has pictures or a more detailed description, I'd appreciate it.