mo u will need the matching map sensor for the ecu aswell,, i.e if u get a fiesta ofab ecu u will need an ofab map sensor,,

also if u use a xr2i inlet and sensors u will need to change the act sensor for a frst one as it will give a false reading to the ecu and make the car run incorrectly..

also i dont know if this has been pointed out, if you do use a xr3i loom u will need to make a few changes to it to run the ecu on ofab..

but if u use a OFAC ecu it should just plug in and run the car..
and also u will need a edis4 module and when u do get one make sure u cut pin 2 out as it is not needed..

if u need anymore help give us a shout..