got it worked out ,had to grind quite a bit on the calipers but got it working.
used the rotors for a 2004 awd astro van
and the calipers from a 99 4x4 Yukon .

 

Good deal. Got my rear wheels from a member. He ran OBS k1500 light duty front calipers and rotors. Said he had to a little bit of grinding. Gonna give those a try.

 

Damn I really like the 18" runners and the rear setup is perfect. Very nice.

 

I run a 15x10 wheel on the back of my truck with OBS rotors/calipers and don't have a single clearance issue. Not that it helps but my back spacing is 6.5" with a 295/65/15 MT dr as well

I got my brackets from Oakley and then Bought all the parts that he had numbers for listed in his post