I have had a 406 td saloon for a few years now and it has a lockable/ removeable tow hitch in the boot. I never needed before now and have no idea how to fit it to the car. Under the boot is the electrics connector and a socket for the tow hitch to fit. My dimness is at its highest has I cannot work out how to fit it apart from hitting it with a slegde hammer. I have the key etc. Help me please!!!