New and need help-'03 Yukon Lift Help

[Holiver]

Hey all, I'm new and need some help. I'm getting ready to purchase some 285/75/16's for my truck. While I'm at it I'm gonna do keys and spacers. I'm gonna get this kit.

http://www.ebay.com/itm/260843332952?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Now I plan on do Bilstien 5100's all the way around eventually, but I just wanna do either the front or back first, then I'll do the others soon. So should I do the fronts and leave the rears for now or will the rears be damaged by the 2" spacer? Or should I do the rears and use the extenders up front?

As far as the bilstiens go, they are somewhat confusing. There seems to be 0-1" lift versions and 4-5" lift versions. As well as part numbers crossing over and such.

So which bilstiens should I use? 0-1" or 4-5"? And what are the part numbers for front and rear?

 

[WildBill]

What shocks do you have in the back? the normal shock, Nivomat, or air? that may help decide what shocks to replace.

I am about 2-2.5 higher in the front and these are the 5100s I have up front.
BILSTEIN 99-07 GM K15 4WD - Part # BIL24-186643

I got a good deal from 4wheelparts .com

 

[Holiver]

I just have whatever came stock on it. So I'm not really sure. I know the ride quality will suffer without putting new shocks in the rear, but will it damage them before I can put Bilstiens on?