It might be cheaper to get a stuffed(totaled) car and start pulling everything out. you need and selling off the restMy thoughts exactly.
Issue then becomes all the fueling and cooling needs.
Ford may sell a harness and ECU??? TBD.
But it would probably work with all stock style components. Adapting to another platform is a good chunk of work.
Great starting point though.
I think the real cost to drop into a fox body with parts and labor would be an additional 40-60K.
Then You have the tranny, rear and suspension. Not a cheap project.