This is on Richard Atwell’s “Essential Upgrades” list for a reason. The following is the process I went through to install the Bosch headlights that I bought from BusDepot.com. You can also correlate this with the Bentley manual (Section 4, Pg. 26, Part 8.1)
Time: 20 minutes
Tools: Phillips screwdriver (Size P1 and P2)
2 each – Bosch H4 Headlight – Part# 0301600118
2 each – H4 halogen bulb 55/60 watt – BusDepot.com Part# 78155
Remove the phillips screw from the inner portion of the headlight trim ring with a size P2 screwdriver. This is the only screw holding the trim in place. The Bentley manual states that the screws are a permanent fixture of the headlight trim and can be used as a handle to pull the trim gently away from the body. My screws came straight out of the trim.
With the single screw removed from the previous step, gently pull in the inner (toward the middle of the bus) side of the trim until it is about an inch from away from the body. There is a lip on the outer side of the trim that latches to the body. Gently move the trim toward the outside of the bus and the trim will clear the body.
Remove the 3 short phillips screws that hold the retaining ring on. Use a size P1 screwdriver and make sure to remove the correct screws. The screw in the middle of this image is what you are looking for. The screw at the very top and bottom of this image are what hold the headlight housing to the body and are not what you are wanting to remove for this project. Also make sure you are not removing the screws that adjust the angle of the headlight.
Pull the headlight away from the body. With the headlight a few inches out, reach around and disconnect the cable connector.
Now we start working with the new headlight.
Looking at the full size image may help on this one also. You’ll see how the retaining clip is locked into place. While pressing down on the extensions of the clip, pinch them together and let the clip come up. It is hinged on the opposite side, so do not expect the clip to come off the headlight completely.
With the retaining clip rotated out of the way, remove the black, temporary plug from the headlight. This is where the bulb will be inserted.
With the temporary plug out of the way, you can install the halogen bulb. There are three extensions coming off the edge of the housing of the bulb. The bulb can only be inserted one way, WITHOUT taking up the slot where the retaining clip locks into place. Neither of the three extensions on the bulb housing should go where the retaining clips fall into place. Once the bulb is in place, lock the retaining clip back into place.
Install the rubber housing around the base of the bulb and press down lightly until the opposite end of the rubber seal is firmly against the backside of the reflector. Once the cable connector is attached, it will help to keep the rubber seal in this position.
Place the retaining ring from the old headlight, around the new headlight. Attach the cable connector to the bulb and reattach the headlight to the body, via the retaining ring. The headlamp as the word “TOP” stamped into the glass. Using that marking, make sure the headlight is vertically aligned. Using your P1 phillips screwdriver, reattach the three short screws that hold the retaining ring in place.
Reinstall the trim ring by reversing the step to remove it. The lamps on these are a bit flatter than the original headlights.