engine sensors, how do I test, then how do I display? Options

[mobymutt]

I have a stock 1.8L engine, but with dual carbs. Since I just rebuilt it, I am now somewhat interested in tuning, and would also prefer if it didn't blow up again immediately.

I have been reading Mblizzard's microsquirt thread and, although I am not planning on moving to fuel injection, I like the idea of having all that feedback to verify engine performance. I also don't have enough background to even begin tuning by the seat of my pants, ie feel, spark plug colour, or whatever else people use in lieu of data.

At the moment, I believe all I have is the stock oil temperature sensor and gauge, which seems to work although the gauge doesn't have any numbers on it.

There also appears to be both oil pressure and head temperature sensors, but they are not currently wired up, nor do I have any gauges for them.

It also seems like an O2 sensor would be handy.

So questions:

1) What's the easiest way to check if the oil pressure and head temp sensors that I have installed actually work?

2) What's the cheapest/easiest way to get readouts? I am assuming good old-fashioned gauges, but unsure how to go about finding the right ones to match the sensors.

3) If I install an O2 sensor (on the muffler like I have seen in someone's recent thread), will that allow me to properly tune the dual carbs? It seems like I have 4 locations for mixture control, so I would then need 4 locations for the O2 sensor?

Any advice, pictures, links, etc would be welcome!