WHatever you read, when it comes down to fitting the external airline to the compression fitting on the pumpkinhousing- bulkhead fitting- make sure you have a wrench on it, so it doesn't turn as you tighten the compression nut.
If it does, you risk compromising the internal seal of same. End result is a presurized axle housing and burping lube out of the breather.
I'd pay an authourized installer so you are sure you have a warranty. Mine blew up after being improperly installed and I'm glad it wasn't some guy in his garage that put it in. If you want though, here's a good link. ARB info