I confirmed my suspicion about these gaskets today.
It took me an hour and 25 minutes from first disconnecting the battery (I had drained the coolant last night) to go from this;





To this;





As you can see, these gaskets are crap too;





IIRC, I've seen other 3300s that were machined front and rear for a counterbalance shaft. This one is only machined at the front of the engine.


I'm suspect oil analysis would have shown a problem.

The displaced gasket surfaces were readily seen on the intake too.





The clean up;





Got to this point at 16:25 today;



Finishing tomorrow should be easy.

Sorry I havent responded, other things had priority. I looked today and NO sign of coolant in oil or tranny.
I wish there was a sign of cross contamination. When running , oil and tranny pressure is more than coolant, but when you shut it off oil and tranny go to 0 and coolant pressure stays for quit a while.
I'll pull the intake next but I hate trying to "read" gaskets.
Actually as thick as the goo is I'll have the radiator flushed and checked first.

I think that'* your best bet, and easier and less invasive than the alternatives.

Transmission coolers are usually on the return circuit, so they usually have less pressure than the radiator.

Does it have an engine oil cooler built into the radiator?

I drained the radiator a few times then added a heavy duty flush and let it run about 3 hours. Then I opened the drain and adjusted the hose to just keep it full while running for a couple more hours I will keep a close eye for oil again.
There isn't an oil cooler on this.

Did it have a lot of oil floating in it before you drained it?

Yes, lots floating and mixed with the coolant.

Black, brown, red, or undecided?

Black floating and the coolant was brown

Sounds like engine oil then, does it have an oil cooler built into the radiator?

Nope, no oil cooler