I will at some point soon be putting a Cognito 4-6 on my truck. Will try to keep it around 4. Anyways I want to get 33/12.5/20 and need to know what backspacing and such I will need to get to fit with my intended setup.

go with 35's with that lift.

you can fit the 33's without a lift

I guess that could be a possibility, so what backspacing with those then?

well the -12 looks nice.

the 33/12.50/20 requires trimming but i think it looks perfect.
thats what i have on order. diamo 16 karats 20x10 with -12 offset on toyo m/t's

+12 on a 9" rim will fit better wthout a lft. With the Cognito 4-6" I doubt it would matter much. Depends on the look you like also.

4.5 BS.. 18x9 on 33s