I swapped a 250 for the 200 in a Maverick (the Mustang is very similar)a few years ago, and I was happy with the change. It wasn't a "bolt in" Like I thought it would be. Tranny, radiator, and motormounts had to be changed, but "stock" FOMOCO parts were available, some won't be in your case. If you have to "adapt" another engine, why not do it with a 240/300. Those engines have far more potential and respond to modifications well. Just an idea.
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