MK5 ESCORT BOXES DO FIT STRAIGHT IN...... YOU NEED THE EARLY ZETEC VDERSIONS THOUGH(STARTER MOTOR AT THE FRONT!!!) IF YOU ARE AFTER THE LONGEST GEARING POSSIBLE,YOU NEED TO GET A GEARBOX OUT OF A MK5 DIESEL MOTOR.JUST REMEMBER TO FIT YOU MK3 GEARBOX MOUNTS TO THE MK5 CASING!!!!!!!!!!!!!