[jzchen]

I use an H9 modified to fit, then carefully adjusted the aim. I only needed to trim a little bit off the tab on one bulb/side. I'm afraid I'm not sure how happy you'll be regarding LED replacements, (or how safe/blinding). Crossing my fingers you're happy with them.

I'm not sure I saw anything to be concerned about regarding leaving the backs open. Not sure if water (in the rare rain that we have) gets to that area to be honest...

 

[jzchen]

Shoot, that’s right we don’t all live in drought ridden CA!

Having replaced the bulbs in the past I remember the bulb having a metal base which mates with a solid metal piece in the lamp. Since there is no rubber gasket like with the oil filter I would have to say that it is not water proof at the bulb lamp interface, that the cover that you are thinking of leaving off does the job of sealing the back. That rear side is not subject to rain and the like as you’re probably aware being inside the closed hood. I forget what material the rear cover is now it’s been a while. One caveat of using H9 bulbs is their very short calculated lifespan. My iQ isn’t driven much though so I haven’t had to replace the 150 hr bulbs yet. I believe H11 the original size in high performance versions are rated in 400 hr range if my memory serves me….

I am of the impression that the front of the lamp is sealed to water intrusion. I take my iQ to one of those touchless car washes that sprays strongly to clean, and moisture never enters the lamp….