Patrick,
Here's the batch job that I use to switch to/from daylight savings time.
I have this job scheduled to run every Sunday at 02:00
It turns out that you don't need MPEX to do this.
You'll need to change the TIMEZONE variable to the correct value for
your timezone.

!JOB TIME,MANAGER.SYS,PUB;OUTCLASS=,1;PRI=DS
!COMMENT ****************************************************
!COMMENT * Change the system clock TO MOUNTAIN STANDARD TIME
!COMMENT * on the last Sunday in October.
!COMMENT * Change the system clock TO MOUNTAIN DAYLIGHT TIME
!COMMENT * on the first Sunday in April.
!COMMENT * 95/10/25 RPT - Initial development
!COMMENT ****************************************************
!COMMENT * This job should be streamed at 2:00 am on the proper
Sundays.
!COMMENT * It will work fine if it is streamed every Sunday at 2:00 am.
!COMMENT ****************************************************
!COMMENT
!showclock
!if hpday = 1 and hpmonth = 10 and hpdate > 24 then
!  SETCLOCK TIMEZONE = W7:00
!  TELLOP *************************************************************
!  TELLOP Changing the system clock to MOUNTAIN STANDARD TIME.
!  TELLOP The clock will S L O W   D O W N until we have fallen back
!  TELLOP one hour.
!  TELLOP *************************************************************
!elseif hpday = 1 and hpmonth = 4 and hpdate < 8 then
!  SETCLOCK TIMEZONE = W6:00
!  TELLOP *************************************************************
!  TELLOP Changing the system clock to MOUNTAIN DAYLIGHT TIME.
!  TELLOP The clock jumped ahead one hour.
!  TELLOP *************************************************************
!endif
!showclock
!EOJ