i have connected a new radio up and it works no prob then when i try and put it in the slot and the back touches the metal surround of the car it blows the interior light/clock fuse
any ideas please how to fix

 

i'd be checking the earths and where they are connected to and maybe move them.
Also check there are no loose live connections hanging anywhere or exposed/loose wires that are coming into contact with either the cage or the surround.

 

thanks i'll have a look