If i were to do a swap with money not being as big of an obstacle i would go 3.5 ecoboost in a heartbeat. But the cost of the motor/trans and cost of a harness and ecu from a donor is 5 times what even a pristine bronco 2 is worth. Ebay has the motor and engine harness right now for around $3000 and up from there. Then trans and ecu with tuning and your at $5000 without blinking.