the mount was put on in 2010, when I completely rebuilt the truck. The first light I installed ,I built from parts of other light I had . I had to disconnect when water filled up the switch housing while on the road ,in a heavy rain . I replaced the whole unit last year with a NOS I found on ebay . When I installed the mount in 2010 , I used marine grade caulk,and bolted the mount to the body. My concern is what stops the water from traveling down the shaft and into the interior. There is nothing more that a bushing , which Ive tried to grease, to stop it from leaking . Ive run out of ideas , short of removing the unit all together . and sealing up the hole . or just putting a dummy light there .