I had IPF800'S. The ballasts were small enough to fit in the light so all I had was two wires coming out the light and they fit directly into the old loom.
If you decided to convert to hid. Dont but the cheap kits. The globe takes longer to warm up, the ballasts are much noisier and the light output is garbage. I spent $150 on a 70w 4300k kit when I converted mine. The result was very good.