01-03 had a projector style housing that was longer. It uses an H3 bulb. This gives a "cooler" appearance and a better beam pattern.

The newer style is just a normal back-reflective housing that utilizes an H11 bulb. It's about half the size.

In order to convert from back-reflective to projector housing, you will need to make a harness that is H11 female to OEM projector housing plug. I think I outlined everything you needed in a thread way back.

__________________