The Prodigy series can be mounted in any orientation from horizontal to vertical and upside down (not sure why). The Primus IQ instructions says: "WARNING The Brake Control must be mounted
from 0 degrees to 70 degrees nose up. (See Below).
In hilly terrain it is advisable to leave a margin at
either extent to keep bars from coming on when going
up and down hills."
The bars they talk about are indicators the controller is too high or too low. Mine is mounted at about 60 degrees up and never had a problem with it.