Installed an ARB (IPF) H4 headlight wiring harness this morning. It was cheaper than the rallylights harness when I bought it and the quality is great. Couple things to note:
-You don't need to remove the headlights, only the headlight bezels to make it a bit easier to move the loom through the grill up to the driver's side headlight.
-The majority of the wiring/relays is set up to be on the passenger side and use the passenger side headlight plug as the trigger. This worked to my advantage as I did not want to use the OEM driver's side headlight plug since it has been causing me issues for the last few months.
-I mounted the relays on the firewall to the right of the heater core box. The relays/relay plugs are very heavy-duty and large so if you have or are going to install a cowl intake, you might have to great creative with mouting them.
-There are three small plugs in the wiring loom attached to the relays. These are not used as ARB included them for Toyota truck applications.
Overall the install was very simple (took about an hour taking my time), headlights work great, and as an added bonus my TJ runs/performs better and starts easier since I cleaned the all of the battery/cable connections at the same time.