[sachaja]

I even pulled the plastic inner fender well but still couldn't access all 4 torx screws. Even if I were to remove them in not sure I would be able to reinstall them once I replaced the bulb.

I was finally able to replace the d1s bulbs on my 2014 LCI 535. It was a PITA but I removed the plastic inner fender, to reveal the back of the headlight assembly. I then removed the plastic side cover in the engine bay , held in by a bunch of "push pins" to access the top of the headlight assembly . There are a total of 5 T-30 screws that hold the headlight assembly in place . 3 up top and 2 accessed from underneath via the wheel well. I then had to loosen the
Msport front bumper ( not remove it ) . 5 screws underneath , ~4 screws up top and 2 in the fender well which attach the fender to the bumper . By doing this I was able to move the headlight assembly far enough forward to access all 4 T-20 screws of the plastic cover in the back of the headlight . Once the back cover is off you can twist (1/4 turn) counterclockwise the D1s bulb out and disconnect the electrical connector. Take note of the position of the electrical connector on the back of the bulb before you remove it in that it needs to be in the same position when you install the new bulb. The D1s bulb has a plastic retainer on it that must be removed and installed on the new bulb. Install the new bulb , it will make a definitive click once it is in place . Make sure the bulb lights before you reassembly everything. It took about 2 1/2 hours for the first side and somewhat less to do the second .