You'd face major challenges including:
* Different engine mounts: The V8 engine will need entirely new mounts.
* Transmission incompatibility: The Mustang's transmission will likely not bolt up to the Sport Trac's transfer case.
* Exhaust system: The exhaust system would need to be completely custom fabricated.
* Wiring harness: The wiring harness would need significant modification or replacement.
* Cooling system: Radiator and cooling system components may not be sufficient for the V8.
* Driveshaft: The driveshaft may need modification or replacement to accommodate the larger engine's torque.
* Firewall clearance: The V8 might not fit under the hood without extensive firewall modifications.
While it's theoretically *possible* with significant custom fabrication and engineering, it would be a massive undertaking, far beyond a simple engine swap. The cost and effort would likely far exceed the value of the vehicle.
