265s = stock wheels
285s = new wheels
Both of my 265 and 285s are the same tire.
I assembled my COs, so they did not come set. My initial measurements can be found in the lifted thread and the measurements with 285s can be found in my build thread. COs can be adjusted prior to install or adjusted when they are installed with some lube and the adjustment tool provided. Adjusting the COs is a one person job.
You are making the lift choice more confusing than it needs to be. OW has a thread dedicated to explaining their lift options in detail and the type of customer they fit.
Here are some additional consideration points
Adjustable COs? allow you to fine-tune your height upfront. OW does not have adjustable COs, icon and toytec do. Also, if you add weight upfront throughout the course of life, you can keep the same set-up and crank the CO up a couple notches to get the ride back to the same height.
How much do you want to spend? Icon is pricey, toytec is more wallet friendly and OW is between the 2
Only looking to level the nose? spacers will level out the nose but will provide a stiffer ride than a whole new set of springs and shocks. Another optoin is to get bilsteins and set the height of them to the 2nd or 3rd height option, this will give a slightly, slightly better ride.
Want to get rid of the nose dive? You need stronger springs up front. While you add stronger springs, you might as well add new shocks at the same time and get the front end done at the same time.
Better suspension? Then you need new shocks and coils all around.
So you want to level it off AND get better suspension? you need new springs and shocks all around. You need to decide 1) how much you want to spend 2) take into account future modifications.
I think the minimum lift icon, toytec and OW offer for the rear is 2in. Look at a ruler, the difference between 1 and 2 inches is barely anything. This is your 4th or 5th thread on lifts, so you are making it more complicated than it needs to be and just asking the same question in different ways.
Why did I choose toytec? Because they are down the road, not too expensive, have adjustable COs to account for the weight that I planned on adding (bumper and winch up front) and the springs are stiffer in the rear which allowed me to add my storage box filled with supplies without sagging the rear.