The factory speakers in a Ram truck with Infinity have the Infinity amplifier attached. That's why there are four wires: two of them are the (+) and (-) speaker wires. The other two are power and ground wires for the amp. You need to connect the signal wires to your Kappa speakers, and leave the other two wires disconnected. You can buy a 4-pin adapter for Chrysler speakers that will make this much easier. Otherwise, I THINK the speaker wires are the two middle pins on the plug, but you'd be well advised to test them before connecting them to your speakers.