How do I convert the HBL503 (5000 Series) for use with 208V?

Turn power on at the breaker. Press and hold SET CLOCK and TIMER for at least three seconds until "Sele dEG" appears. Press and hold STOP TIME and TIMER for at least three seconds until the display is blank. Press and hold COOK TIME and STOP TIME for at least three seconds until "VOLT 240" is displayed. Press SET CLOCK, then press + or - to select 208V. Press SET CLOCK again, then press and hold STOP TIME and TIMER for three seconds until "Sele dEG" appears, then press and hold SET CLOCK for three seconds until the time of day clock appears.