By default the Driver Station starts the Dashboard located in
C:\\Program Files\FRC Dashboard
with the default name of "Dashboard.exe"
You can replace this default dashboard with your own by renaming yours and placing it in that location.
Alternatively, not practical unless your Driver Station is also your Programming laptop,
The LabVIEW button on the Driver Station Setup tab looks in:
My Documents\LabVIEW Data\builds\FRC Dashboard Project\FRC PC Dashboard\Dashboard.exe