The shop that installed my Moper lift said they would not install spacers on top of the lift because of the geometry issues. If you want more lift buy a higher lift kit.
I'm just putting this out there...Jeep must have a really inaccurate mpg configuration in its system because there no way someone is getting 20+ mpg on 37s or 35s and someone else is only getting 12-14ish. Enough already...some guy on here actually stated 18 average pulling a 4k trailer.
I average 17mpg with no trailer and no load. There is either something wrong with your trip computer, your calibration or how you calculate your fuel economy. Sorry 18 mpg is just not possible with a trailer.
The BFG KO2 315/70R17 C is what I'm running. They are the stock wheel for the Ford Raptor so they were design more around a light truck tire vs. a heavy duty tire. They measure out right at 34" on 17"x8.5" wheel.
Just to clarify it does not fit 100% with the soft top left on in the safari style position. When the soft top is totally removed it keeps water out....so far.