The eecv doesn't control much of the car ons ford at this age. This is done by the gems/ body control ecu. And a seperate ecu for the abs.

To get the ecu running you will need the matching rdif chip found in the key from at least one key.

This is for the pats. No key and the ecu is a paper weight.

To getting it running well, match the sensors and spec of the engine to the ecu tune.

Sensors and hardware you need.

Injectors
Crank sensor
Cam sensor
Tps
Charge temp sensor ( seperate from the maf on an rs)
Coolant temp sensor
Maf (same as st170 and st220)
Map (2.5 bar same as diesel)
Pre and post O2 sensors (any zetec)
Coil pack (any zetec)
Boost solenoid (same as mk2 st or gm ie saab/vauxhall)

It also likes to see a dozen other signals

Speed
Clutch
Throttle Wot
Ac low pressure
Power steering high pressure
Canister purge valve
Telemetrix
And more but you can get around these.

I would avoid chopping up an rs loom. An st 170 loom can be adapted and is 1/5 the price.