Hey Florida Brother!!
I have no experience with a locker install on a 4th, gears and an ARB were in the plans, but you know..... put on hold for awhile until I can get back to work.

I did only the ARB locker on my 5th Gen back in July of 16'. I was headed up on an extended trip to the NC mntns to see some family and then on to Rausch Creek, PA for a 3 day weekend at the park.

I had already picked up the locker and compressor in a Group Buy (Total Automotive Performance in Vegas) and had the compressor w wiring already installed to save a few bucks. So on the way up to PA, I stopped in Raleigh and had East Coast Gear do the install of the locker and a steel braided air line. Good customer service up there, with a decent waiting room and a TV. Took them most of the day, 6ish hrs I want to say.
Very happy with the locker's performance up at Rausch that weekend, never had a problem, and it's still working well.
Don't know what your plans for the compressor are, but here is a mounting solution I came up with on my 4th gen. I have a similar mount on my 5th gen and it's been solid.
4th gen ARB onboard compressor mounting bracket-CHEAP how to

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