At configuration time only of any Program you will have to designate one of the newly created routines (ladder files) as the "Main" routine (Assignment); within a Logix system, only the "Main" routine will be automatically scanned (it is the equivalent of LAD.2 for the PLC/SLC systems); there (within the "Main" designated routine)you will have to JSR to the respective Program's other routines.
In your case, since you cannot assign the Main status to an already created routine, I would add another ladder type routine, this time specifying the "Main" type at configuration time; once in the project tree, within the newly created Main ladder logic routine, add two rungs each containing a JSR instruction "pointing" to the previously created two routines.
You could also delete one of them and then re-add it, this time with a "Main" assignment.