I bought these but have decided to go a different direction. The kit is in near perfect condition with hardly any use. The rotors have been checked for runout and look great. Wilwood Dynalite Drag Race Rear Disc Brake Kit for 12 bolt Chevy 11.44" dia solid rotor w/2.81 offset, "C" Clip Eliminator. These will also fit a 8.5" 10 bolt according to Wilwood. Wilwood Pt # 140-4545B. $375
http://www.wilwood.com/PDF/ds255.pdf
http://www.wilwood.com/PDF/ds255.pdf