Thanks guys, and Wolfgang for the gauge info as well. "G" on the sender goes to "G" on the gauge, pretty easy and smart.
Whenever I use multiple senders I use the bolt down MGB oil line "T" and braided stainless hoses to do the job. The MGB oil line hoses are long enough to reach the side engine bay tin (or a fabricated stationary body mounted shelf,) the "T" has a tab for the bolt and the senders can be set up pretty cleanly. We've run this on the drag Beetle and the BMW SCCA car. Easy Peasy.
Gotta post on the Fiat Forum next to find out what the four lights to the left of the speed pod are for . . . then there are those two suspicious toggle switches to the right.
Honestly, EVERYTHING about this Fiat is suspicious and creepy. It looked like a haunted house when I got it, all rust and dust and dirt and cobwebs and hangy-downs, and the rust was that deep rot/rust sort that's multiple layered through three layers and WET! I power-washed in and out, hung it from the winch and began cutting on it. Results were an empty shell with everything from the rockers on down cut away. No floor, suspension points, door sills, lower quarters, glass or interior, front or rear valances, doors, deck lid or hood.
But now it's clean as a whistle and all in metal etch primer with new body work nearly done. Sitting up on sawhorses . . .