I just want to make a post in this thread too, even though we've been PM'ing.
the ekstensive kit is a nicely built, easy kit. not much thought has to go into it. cut all the shit off the frame, line up the square holes and weld the shit on. passenger side you have to cut a section out of the frame rail so the bracket can lay flat.
however, the fact that the bag brackets are mounted for you already means that in order to get full lift while using the same oem spindle, as they claim, would mean that every wheel size is irrelevant. it would be going off overall tire diameter. that is, if they even care about you getting full lift if you run smaller wheels than tires than 33.5" (275/25r28). everybody concentrates on laying and how that looks. you don't drive laid out. you concentrate on have the best camber curve from 1" frame clearance to 1" over the tire. whatever size that may be.
MMW budget arms are awesome for anything 29.5" and smaller tire diameter. A 285/35r22 specs out to be 29.8". wheel width compared to section width ofthe tire has an effect on overall diameter, which may be why you're getting 31", but I'm not going to say that you're tires don't measure out to be 31" because i know my 275 (10.8") on my 24x9 are 31" overall. a 275/30r24 is only suppose to be 30.5".
the ekstensive kit is nice if your wheels are not a high enough offset to tuck and you need the extra 1/2" per side. otherwise, 1" per side should be the most you go in the front.