te Escort bottom end (unless its a very late one) won't have the hole and flywheel for the crank position sensor so you would have to use the Sierra bits as RSTski said

you'd be able to keep the loom but you would need the OFAC FRST ECU, MAP sensor and EDIS module and change one wire. If you wanted to use OFAB instead there will be a few more wires to change

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