coolant in oil

It could be is the timing cover housing. The water passages that go through it get corroded & it will leak there also. That happened to my Duster once. I changed the head gaskets & they didn't look bad when I changed them. Ran it for a day & it was full of water again. Was gonna pull the heads again when my friends dad that worked at dodge in the late 60's & early 70's said to pull the timing cover & sure enough it had pits in the coolant passages.