12v Rocker Switch Housing Plug

thingiverse

This is a plug to fit loosely, but securely in a standard automotive rocker switch receptacle (.87" x 1.06"). If you want the fit tighter, then you can scale it up a little bit. There is a clamp on the back if you have already run wires (5/16 dia hole) and there is a version without a hole that you can drill or model in whatever diameter you need. Use a pair of 6-32 x 1" screws with hex nuts to secure the clamp if you are using it.