Help with new gauge setup

One perk of living on the West coast, I can post a question before bed and get an answer in the morning! Sounds like either #2 or #3 is the way to go then. I'll try to get a pic of the oil sender to verify that I'm looking at the right thing there too.

Out of curiosity, what is that Thermal Vacuum Switch supposed to hook up to, a vacuum source and the EGR?