Well,unless you've got access into the Ford Engine Management (assuming your not using DsF or another ECU its a bit difficult. Idle speed is controled by the PCM/ECU with A PWM signal adjusting the ICV.

It possible to carefully remove the sealing putty from throttle stop screw on the TB so that the fixed physical bleed at idle became adjustable to give the ECU/ICV an easier job. I had to also change the cable bracket screw to a c/s one to be able to get an allen key into the stop adjust.

Martin