It's not clear what exactly you mean.
You can run two neutrals next to each other as long as you otherwise abide by electrical codes regarding the limits of conductors in an enclosure and gauge size.
You can also use a single neutral return for two circuits if those two circuits are opposite phase, since the net result will be that the neutral never carries more than a single circuit load and may sometimes carry less or even nothing if both circuits are in use.
There should be 2 or 3 wires. A hot, a neutral and sometimes a ground.
If you mean 2 bare copper wires those are the ground wires. Tie them together and then connect the light fixture ground wire which will be green or bare copper to those ground wires.
Your 2-wire system is actually connected to one "side" of the 3-wire system. In your utility's 3-wire system you have 2 hot wires that are attached to each end of a tranformer winding and the neutral is attached in the middle and grounded. Typically in the US this gives you 240v (or something similar) between hot leads and 120v from each hot lead to neutral or ground.
You could solder them together and then tape securely with electrical tape.
Black/White/Ground power in and the same out. Tie the incoming and outgoing white wires together under a yellow wire nut and push them back in the box. Tie the ground wires together under a green wire nut and connect the pigtail from those ground wires to the ground screw on the switch. Connect the 2 black wires you have left to the 2 screws on the switch. Doesn't matter which black wire you connect to which screw.
Disconnect the 2 wires on the switch and tie them together
Disconnect the 2 wires from the switch and connect them together
Your black wires are your hot wires. The white is your neutral or common. It would be best to run an equipment ground (green wire) too.
Neutral switch
Tie the 2 wires together and see if the vehicle starts - if it starts now and didn't before switch is bad
if your converting your truck to manual/stick transmission youll have to join the 2 wires that connect to the neutral switch uaually found at the bottom of the t-bar theyll be the same color (simply cut and solder/join wires together)
There should be 2 or 3 wires. A hot, a neutral and sometimes a ground.
The two permissible colors for neutral conductors, according to the NEC, are white and gray.
4 wires. 2 hot legs, 1 neutral leg, and 1 ground wire.
Your old wiring has 2 "hot" wires and a ground. Your new appliance needs 2 "hot" wires, a Neutral, and a ground. Please consult an electrician.
Hot and neutral, or hot and hot, plus ground. (2 + 1) 2 hots a neutral and a ground 3+1
A 220 vac circuit has 2 hot wires and a neutral. The neutral stays at 0 volts and the hot wires vary between positive and negative. When one is positive, the other is negative.