I broke the mounting tabs on my driver front headlight so I'm trying to save some money and see if the black plastic housing on a wrx or 2.5i would work. Does anyone know if the black plastic housing of 06/07 headlights are all the same across the models? I know my STI has the extra leveling motor and HID modules, but I would think the housing it self is the same.
Can't say for certain, but I'd imagine they're all the same. There's nothing in the WRX headlight that's any more special than what's on the Impreza.
The primary difference is that the bottom of the non HID headlights will need to have a hole drilled to allow the ignitor wiring to pass through to the rear of the xenon bulb. However the screw holes should be present for you to screw the ballast to the bottom of the headlamp. The "cap" on the rear of the headlight will be different but you should be able to salvage that from your old headlight.
I have an 06 Sti headlight that was taken apart for parts I can sell you what you need. Pm me a pic with the part of the headlight you need to replace if your interested and we can go from there..