Adding second AC to GD 3170BH

So at some point, I am going to add the second AC to our GD 3170BH. It is "pre-wired" whatever that means, but I assume it is just the electrical that is up in the ceiling cavity.

So anyone on here with a 3170BH that has done this... Does this unit have the ducted AC going to this area, or will the second unit just need a standard diverter. Also what about the thermostat?

At the end of the season, I will probably pull off the trim on the vent and take a look, but if I can start to prep sooner that would be great.

Thanks!