You could pair them together, but you would need to provide relay switching between the two. Not only a relay that switches the antenna input, but also mutes the receiver during transmissions. Even after that’s done, it will be difficult to track the two together on SSB. It would be similar to having a locked clarifier that covers the entire CB band. There’s methods or mods you can do to create a “zero beat” signal that would help align the two, but that’s an old school tedious endeavor. Pairing oddball separates was the norm on AM and CW years ago. After SSB became the mode of choice, having full transceive capabilities on a single VFO made operation so much easier, let alone achieving an accurate alignment. IMO I believe the SSB transceiver greatly helped skyrocket the popularity of that mode. If I owned a Kenwood T559 I would be looking for the matching R559 receiver. A great set of twins. Those two coupled together are capable of sharing either the VFO on the transmitter, the one on receiver, or you can keep them separate for frequency split operation.