You might grab your VOM & start ohming em & see what wires on the other ends are hot. Need jumper wires with alligator clips (I make up several long ones for general work & they would work fine for this) & I always pull a batt cable before I switch the meter to ohms so the only power is coming from the meter battery.
That's really the only way to know unless it's spotted visually. The battery has to be disconnected before ohm checking power wires to ground.
