In an ordinary videogame, everything you can interact with is either assigned to a hotkey or visible on-screen.
In Full Motion, that isn't always be the case because not everything you can interact with is always on-screen.
So, why not have the controller rumble when you "mouse over" an object not visible on screen? It could even rumble a bit more when you "select" the object. Both of these would serve as a sort of tactile "screen" for object selection.