Success! I appreciate all of you who have posted with suggestions and links to prior discussions - I tried them all except the Pine Sol, and that’s because there was none in the house and I got it unstuck before buying some - but I will use that in the future for sure.
At the end of the day the key was my neighbor came back from vacation and getting access to his really good work bench and vise set up and then threading the bolt in about halfway and using some hardwood on top to take the hammer blows. After about 5 strikes we heard it move and then a few shots to the side of the stem and free at last. You can see in the picture there isn’t much rust so kind of a mystery as to why it was so tough to get out.
I’ll be posting the complete bike all shined up later this week.
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