soup dude. thats what mech means. the model has nothing to do with it unless its a flying unit. so lifeisontheline, just go to object editor and edit the 'stairs' it wants to walk on so its 'walkable value' is true. then just order your unit to move up the stairs and it will be on top. And yet, if it is a flying unit and you can't change it in object editor, then its a long hassle of changing flying heights to correspond with the stairs. so yeah, possible.