I ran it wired from the radio fuse with a tap for a while. Then I switched to a direct battery power source with a relay. For all my other accessories I installed a separate fuse block behind the glove box with its own 8g power wire.
If you need help wiring let me know.
would you be talking about something like this, might be good with the gauges i will eventually install
http://www.wiringproducts.com/contents/en-us/p349.html