FINALLY found a good 250 head for my 70 K5. Cost me 163 bucks delivered to my door. Supposed to have only 1 hour run time since complete rebuild. I'm jazzed. Been running on 5 cylinders for months, trying to find another head. My old truck sounds like a popcorn popper going down the road. Narrowed the problem down to # 6 cylinder. Stay tuned for Saturday's head swap trilogy!