I'm running 15" wheels on mine. The 8 lug 44 front uses the same brakes as the 60 so it would be the same for both. I had to grind a bit off the caliper brackets but only because I have 8" wheels with 4" of backspacing. I've seen people run 2.75" backspacing without any grinding.

 

Oh and here are a couple of pics of it with the full widths. And the steering was only temperary got that OTK now.

 

What kind of axles and size tires do you have on your jeep xjmarc?