Topic: Help with wiring basics

[83MT]

Ok, what I'm specifically trying to do is get the oil & volt cluster which is a separate cluster on my '83 to work. My truck did not come with one from the factory, so I'm figuring out how to wire it.

I have the electrical diagram from the FSM, but I don't really know how to read it. What I know is that each gauge (oil & volt) has 4 wires coming out of it. I gather that two are for the illumination of the gauge, and two are for the actual gauge to work. Can I assume one of each of those is a ground? Obviously I can figure out what to do with the grounds, but I have a couple other questions. First, what in the wiring diagram will tell me which is + and which is -? Second, once I know which are the +, what do I hook them into? The + for the actual oil gauge to work I will wire straight to the SR5 oil sending unit (no?). The + for the volt I wire to any hot wire? Then I need to tie my illumination + into a "key on" wire so I'm tied into the dash lights & dimmer. (right?)

So my biggest question I guess, and sorry for being such a newb, is: how exactly do I tie my +'s in to the system? I mean do I strip some plastic off a wire connected to "key on", and splice in my + wires for the illumination? If so, how do I locate that wire on my truck? How do I tell which is a "key on" wire? I know that if I knew some electrical basics this would probably be an easy thing to figure out, but I don't, so...

Last, once I get all this figured out, what gauge wires should I use?

Anyone?

[Duffil]

you need to run power from a switched source to the positive side of the gauge, and the neg side goes to the sender. The sender is always the ground side of the circuit.

on the lights, tie into a wire that becomes hot when you flip the headlights on, otherwise they will be on anytime the key is on.

[83MT [OP]]

Ah, negative side to the sender. Great, thanks. That makes it easy to figure out which is the positive and which is the negative, then, since my diagram does show me which wire goes to the unit. 

Now...after a friend and I looked up some electical diagram things online, it looks like one of the symbols between the gauge and the sending unit is a resistor? There are also two other symbols I haven't identified yet...but is it safe to connect a wire straight from the gauge to the sending unit?

[83MT [OP]]

Nevermind on that last part, it looks like the SR5 sending unit has the resistor, diode etc. built in, so I should be able to run a wire straight from the gauge to the sending unit.