[DeadheadNM]

The crud is like scale and can be seen staining the water passages in the heads that orange color. The water pump is new, the heater core was a correct NOS piece and an original Harrison four row radiator was recored using the OEM tanks. Typical green antifreeze diluted 50:50 with distilled water. I’ll get the impeller checked. As an aside, I did confirm that the intake manifold heat shield was indeed removed to clear the carbon deposits deep to it.

Thanks for the link to the heads. These are well reviewed. I’ll await the crack check and go from there. Wonder if these are still USA made.

The camshaft was deemed to be free of any defects but I’ll double check the thoroughness of the inspection.

Thanks again for the help!