I put the PWM in for the low beams only, did not try it without. The high beams plugged in direct, no flicker on either. They made it look a little easier on the HR videos than it is, small skinny hands will help, but not in the cards for me. I opened up the wheel wells as well as removed the airbox on passenger side and grounding wires on drivers side. It is real tight from the top. I needed two hands to unplug the connector. One hand through the wheel well, the other through the hood doing it by feel. Patience and beer is the best way. Shoving the driver and PWM module in the housing took some patience as well but it all fit. It took me 2+ hours only because I got frustrated and had some more beers. The high beams are easy, except I had to clock the bulbs to get them vertical. Not necessary for the low beams.