OK, I just pulled the head on my /6 that was overheating (see head gasket snafu). The first thing I noticed was that there was no obvious breach in the gasket or head/ block. The next thing I noticed was that the gasket was blocking some water passages in the head/block, above and between cylinder #3 & #4, and above and to the front of #6. I remember reading not to cover these holes. The only thing is, could this account for the crud in the coolant? Living, learning- slowly.

The larger "core holes" in the block's deck, up front by #1 and between #3 & 4 are covered by the head gasket. The 2 large holes at the rear need to allow coolent to flow up from the block and into the cylinder head.

In general, most of the coolent will flow thru the block, to the rear of the engine, then pass up and into the head, where it flows forward and out into the radiator

There are 6 small holes in the deck, positioned to allow cooler block water to flow up and around the exhaust ports in the head. These holes should be checked and cleaned-out. I drill these small holes to the same size as the hole in the head gasket in order to allow full flow.
DD

Thanks, sounds like that was not a problem. I just took the head to my machine shop for a clean-up. I'm going to clean everything up and re-install, maybe torque to 80 lb/ft hot, and hope for the best. The guy at the machine shop said it didn't look like it was leaking.