wheel well back spacing and fender spacing

Hey guys,
I'm playing the waiting game on my '16 OR DCSB and in the mean time I'm spending too much money on parts for it that sit in the garage waiting for a truck to go on. It is supposedly arriving around the 12th of April and the wait is killing me.

Anyway, I've been reading this forum for weeks now trying to learn as much as I can. In all my searching though I haven't gotten a clear answer on wheel spacing. I will be putting on a rough country 3/1 lift level (I know a lot of people will have a problem with this but that's a different issue). I am looking to run 18x9 wheels, with 275/65R18 tires most likely. My question is what is the required backspacing to clear the steering and suspension, and what is the distance from the hub to the fender? From my reading I'm assuming I need to go with 4.5" as the safe backspace, that means the wheel will stick out 4.5" from the hub with probably about another inch in tire. Would that stick out past the fender? If so, by how much roughly?

I know people like to say "use the search", so I will say that i have and I've read hundreds of posts looking for answers. Unfortunately most of the posts end up being very specific. I think a general measurement guide would be great. Something like - if you have an "x" inch wide wheel, the backspacing needed is "y" and over a "z" wide tire runs the risk of rubbing. I know the wheel diameter plays a part too, could make for a really cool table/spreadsheet for reference.

Thanks everybody, any feedback would be appreciated. I'll be contributing to the Inferno color thread as soon as Cinder shows up.