Electronic conversion mopar distributor

The box will plug right into your existing setup and operate fine HERE IS THE DEAL

Your old harness, with a dual ballast, was set up for a "5 pin box" The box you have in the car may or may not be a 5 pin box

The harness/ dual resistor will operate with EITHER a 4 or 5 pin box

Your new box with a single ballast is a FOUR pin box

A four pin box will operate with either a single or dual ballast/ harness
An older five pin box MUST have a dual ballast/ harness

YOU CAN NOT TELL a 4 from a 5 pin box by looking because SOME 4 pin boxes have 4 pins, and SOME 4 pin boxes have 5 physical pins.