start your truck and have someone hold a rag over the tailpipe, if it is an exhaust leak you while hear it pissing out.

 

drowssap - yep, thought of that one yesterday and that's what put me over the edge. Ordered the head gasket kit and bolts. Started the tear down tonight. I will get the heads milled also. Might as well get it done. Luckily it will be in the 30s and 40s this week so plenty warm in the garage.

Thanks to all who responded!

 

So, I went ahead and tore it down. Blown head gasket right where I thought - right behind the number 4 cylinder. I mis-identified it in my original post. The good news is there was no damage to the head or the block but the gasket was shredded. Taking the head to be milled tomorrow - $44 per head at Wagamon Brothers in MN.

The tough part? The number 1 bolt on the left head. Holy ****! Same thing with the number 2 and 3 bolts on the right head. Other than that, about 5 hours to break it down. Used this write up: Engine Refresh (top end) « PaulP38A.com and the Rave manual. All has gone so well far.

Thanks again for all the input everyone.