I have Peak Summit? I think it was called with the tube style UCA not the super expensive aluminum (you have to call/email them for that option) with the 1" block rear. I have an issue with peak on the u bolts for the rear being square, they say no problem but factory is U shaped so I went to the local suspension shop and had them bend some U shaped like OEM and replaced but that was the only issue. Went with 285/75 18 Ridge Grapplers on stock ZR2 wheels and the Bora 3/8" spacers and scovel lug nuts so I dont have to change any of the factory parts on the hubs and I still had minor rubbing on the fender flare in reverse only.