An auxiliary instrument having an open ended back casing is removably mounted on an automobile dashboard in a visible position by a friction spring clip assembly affixed to the dashboard surface by an adhesive layer. The friction spring clip slips back over the back edge of the casing and extends into the open back end to avoid any protruding structure on the casing, which is thereby removably held in place by the simple expedient of frictionally forcing backward into the spring clip.
An adaptor case for mounting instruments on a mounting surface. The adaptor case has a side wall support extending from a base plate. The side wall support receives and supports the front portion of the instrument. The base plate can be rotated for mounting the instrument in either an instrument protruding position in which the instrument extends outwardly from the mounting surface or an instrument recessed position in which the instrument is recessed inwardly of the mounting surface. A retainer bracket securely mounts the instrument to the mounting surface regardless of whether the adaptor is mounted in the instrument protruding or recessed position.
