When I started mine there were a few guys in the States doing them using a "Bolt in" kit, the kit I bought some parts off.

There was one guy I believe who worked for Ford, but not in ECUs and was trying to get the Mustang engine ecu to communicate with the Focus dash.
I think he got quite close but I never saw the outcome.

Aftermarket ECUs have moved on a long way since then so you may find an ECU that will run the Toyota engine and give outputs suitable for the Focus gauges.