I agree. I'm stumped. A /6 should be the most simple to figure out and make run. Vacuum leak would have to be pretty big to act like it does and therefore should be no problem to find but it evades me. Like I said the head is now off and waiting on a new gasket. Napa says the closest is in Indiana. Who would have thought a head gasket for a six would be that scarce. when it does start it is really low on power and won't pull it's self like a jumped timing chain. The exhaust is a straight shot to just behind the cab.