I have only fitted a single channel to a Triumph TR for the horn.
The transmitter card is only the size of a postage stamp, so there might be room?It would only need one battery pack. The set up procedure involves pressing a small button on the receiver card at the same time as activating the transmitter to pair the devices. I would imagine they would be unique, but you might be best to contact the seller on eBay USA. He is in China, but he will respond.
