To change the print option of a procedure, change/create the printer definition of it in PDEF.
For example, in the UI form Procedure Hook, when a process is called via a procedure statement
PROCEDURE STMT 'SAVE.LIST ':V.JSPARAMS.ID
PROCEDURE OUTPUT 'XPROC123'
PROCEDURE STMT 'GET.LIST ':V.JSPARAMS.ID
Go to PDEF, change/create the printer XPROC123 to set the defaults, such as Output Device, Page Width, Page Length, etc.
