I woke up bright and early this morning and decided to tackle the head gasket job. It went better than I expected. I took it slow and careful, since I had never done a head gasket on a diesel before. (a shop manual is a wonderful tool!) No surprises, and the engine looked better than I expected. I checked the head for flatness after cleaning it and the thinnest feeler gauge I had was .002". It was flatter than that in any direction. The shop manual said the limit before resurfacing was .004". I started at 7:30 AM and was riding on it by 3:30. PB blaster is great stuff BTW. The exhaust manifold nuts I was worried about didn't give any problems at all. I ran it for a couple of hours and it's dry as a bone. The cylinders had very little wear. I could just barely detect a ridge at the top of the liner. Push rods looked great and rocker arms were fine. Thanks for the replies!