Mercruiser 165 water in oil help please?

[johnsland8]

I recently purchased a boat with a Mercruiser 165. The PO told me the oil was contaminated with water and he suspected a cracked block. I figured more likely to be a blown head gasket or exhaust/intake manifold problem. I pulled the exhaust/intake manifold and head off of it today. The manifold was full of water but no obvious signs of where it was coming from. When I pulled the head, cylinders 1 & 6 both showed obvious signs of water contamination with surface oxidation, etc. Cylinders 2-5 looked perfect. Again, there were no obvious signs of where the water was coming from. The head gasket looked to be in decent shape and there were no obvious signs of a water path.
Does anyone have any thoughts on this?
Does the fact that there is water only in #1 & #6 indicate anything?
Thanks in advane for any help anyone can provide!

-John