What is this 'add a circuit' & how does it work?? can you show us apicture or what you are talking about?? Are you look to use this 'add a circuit' to run power to a device, such as lights or aux device?? Do you want constand power to your 'add a circuit' or just when the key is on??.Eric said:Thanks for the offer, but I'd rather use the add-a-circuit.