After rough setting the body on the frame I took some measurements to determine the proper backspacing for the wheels and tires.
There is 6.5" from the inside of the wheel well to the rotor flange.
There is 6.5" from the frame (shock lower support) to the rotor flange.
So looking at the FFR recommendation for 6" backspacing seems to be incorrect at there will be additional 0.5-1" of tire width that has to be added to the backspacing.
Currently I'm planning on running 20x10" 5.5" backspacing with a 0.5" spacer (if necessary), with a 295/25-20 this will result in a tire width of 11.6" and a tire height of 25.8"
11.6" on a 10" rim will result in 0.8" on either side of the rim.
5.5+0.8 = 6.3 - 0.5 (spacer) = 5.8"
This should give me 0.7" clearance to wheel well and frame
Almost. A 10" wheel is actually 11" wide overall. 10" inside, bead to bead, with 1/2" flanges. Backspacing is measured to the outside of that flange, so your tire should only overhang the the wheel by 0.3" per side.
Almost. A 10" wheel is actually 11" wide overall. 10" inside, bead to bead, with 1/2" flanges. Backspacing is measured to the outside of that flange, so your tire should only overhang the the wheel by 0.3" per side.
Thanks. I was unaware of that detail. So the 6" backspacing may be close. I bought the 5.5" backspaced wheels. should give me enough clearance and maybe without the spacers.
The FFR max recommendations in the manual are bang on. You can go max 6" backspace on the rears. Here's a helpful diagram for what DoBoy was mentioning above...