1. Width: ignoring any frames measure from brick to brick in three places.
2. Height: ignoring any frames measure from floor to bottom of lintel in two places.
3. Pillar width: from brick face to returning wall
4. Top roll height: from bottom of lintel to first joist or ceiling
5. Motor side: looking from outside the garage in, this is normally nearest your plug socket.

Do you have any other entrance to your garage, if not then you will need an external override