I do not think it is possible. You would need to see if the loom was in place first. Maybe it would work if the option was enabled in the software. Not sure if you can have front sensors without park assist.
For what it would cost I would invest in after market sensors and put the control unit under the dash somewhere. You could enable them from the reverse switch on the gearbox or a switch in the car.
I did when I bought it and apparently can only be fitted from factory and the only ones ford will fit are after market ones with an aftermarket switch on dash and doesn't connect to the park pilot display