Does anyone know what is the hole size for a standard cigarette plug? I want to drill & install a second cigarette plug right here and I don't know what tool do I need to cut the hole.

 

If its the same hole size as the one on the left. Just measure it and mark the Measurement to were you want the hole. Or trace the hole on a peice of paper and trace it on the the spot were you want a cut it out. Run 12 volt power if you want it to work constant or tag it to the accesory wire if you want it switched. Make sure you fuse it. and then ground it. DOne

 

you could drill it out smaller and use a dremel until it fits.

 

Or you could get a step bit and drill it out till it fits.