"They can sell the Mexican-made Focus for $18,000 and make more money than they make on a US-made Focus that is sold for $20,000"
Here's the question nobody seems to be asking ...
If they are renovating and updating a plant in Michigan for $600 million instead of building a new plant in Mexico for $1.6 billion, why did they ever consider opening the plant in Mexico in the first place?
I'll tell you why I think this is the case (and this is an opinion that is not a professional one but is more than wild speculation): The Michigan plant is going to be smaller and produce fewer cars than the Mexican one. And the reason for this goes all the way back to my first post. Ford would be perfectly fine selling 30,000 Focus cars next year -- or even discontinuing the line completely if they could convince all those customers to buy Fusions, SUVs, trucks, etc. Up until now, the EPA wouldn't let them do this. With Trump's election they are likely convinced that the EPA will be changing its tune dramatically.