Any problems with ARB diff. cover installs?

[ncflyer]

I have a JKUR 6spd with 4:10 gearing. I'm considering adding these to the mods and when asking ARB about them, they said with the 2012, they may not fit certain gearsets but could'nt say for sure which. Wondering if anyone has done this and had any issues resulting in needing to mod them a bit on the inside to fit.

Thanks