Required Backspacing and Offset with 3" OME lift

Hey all! I just installed a 3" OME lift on my Tacoma and have been looking into buying Fuel Beast Rims with the machined finish (http://www.fueloffroad.com/beast-d564-w-19186.htm). I am completely lost as far as measurements with the wheels goes. One of my good friends recommended that I get the 17x9, 6x5.5 wheel with -12mm offset and 4.5in backspacing. I plan on going 285/70/17 with cab mount chop performed. What I would like to know is: should I get the +1mm offset or the -12mm offset? Does the OME lift require specific backspacing and offsets? I am looking at purchasing through carID and they automatically assigned the +1 offset with 5in backspacing in the cart when I wanted to purchase. Just wanted to double check! Thanks

 

You'll want the -12mm offset. Your wheels will stick out a bit because they're 9" wide but to run a larger diameter tire (285/70-17) you want 4.5" BS to clear the UCAs

 

You want 4.5" to 4" back spacing. Use this to guide you.