this is thre info i had

A list of parts required for Converting a S2 ERST to EFi, using the XR3i Loom method:
OFAC Fiesta turbo ECU. (OFAB can be used but takes a little bit more work, and will be discussed a bit later)
Ecu related MAP sensor. (OFAC ecu will need an OFAC MAP sensor)
Fiesta turbo engine, or mixture of adapter plates and a trigger for the CPS.
EFi inlet manifold, throttle body and charge carrier
ACT sensor, from the fiesta turbo
Throttle body to charge carrier pipe, still available from Ford at the moment!
EFi flywheel, Fiesta RS, XR2i, XR3i (EFi)
XR3i EFi whole loom
XR3i Throttle cable and pedal
EDIS Module and coil pack etc from XR3i (or Fiesta RS)

NOTE: All of the below assumes you have the XR3i loom fitted, along with all associated EFi items, such as coil pack, VSS (vehicle speed sensor) ect:
Fuel Tank/Pump & Supply
The standard S2 fuel tank and pump can be retained. If your using the XR3i loom, you will be able to just adjust the wiring at the rear accordingly. And connect the fuel lines in the engine bay, using suitable connectors for the supply, and return on the fuel rail.
Personally I used a new 1990' XR3i fuel tank and fuel lines. I took this opportunity to upgrade to an Escort Cosworth fuel pump, as it is a direct replacement with this tank. It also meant all the fuel lines at both ends marry up perfectly to the tank and the fuel filter and fuel lines.