74 duster map light

I have had the map light tucked up under the dash for the last decade or better. Im working on the interior and decided i would get it working again.

Its hooked up and works fine, but im lost as to where it exactly mounts. I know it goes on the passenger side, but i dont see any holes in the dash that will work or line up.

Am i missing a bracket that it is suppose to hook too? I have the plastic socket and somewhat of a bracket built into it. If anyone has pics or could explain exactly how it is suppose to be, it would be much appreciated.

Thanks