Adding Kenworth gauges

2002 T800 I'm looking to add:

- Amps
- Front diff/rear diff/transmission temps

How do I hook up the sensors for these? Putting in the gauges is easy enough (thank you Kenworth!), but the sensors are another thing. I found leads under the dash for the front diff/rear diff/transmission temps but I can't seem to find them where the harness would plug in at the frame. So I'll probably just run new wires. How are the grounds done on the diffs? Do I somehow ground to the sensor? If not, how? I noticed I can do the rear diff fairly easily, as the leveling valve has extra holes. The transmission shouldn't need a ground.

With the amps, how does that work? I know old school amp meters literally took the hot line from the alt to batteries and spliced into it. I don't think that's a good option. One terminal says "alt" and another says "batt". Somehow I don't see 150+ amps going through those itty bitty terminals, so I'm guessing it's a parallel rather than series hookup.