Hi, Yes. I can see the hose. There is also some wire hanging, not sure if its 10 gauge but i will test tomorrow with the switch turned on. The thru hull is covered with a plug.
I suspect your boat has a similar setup as ours, which is a hose connected to a tank stand pipe that leads to a wye fitting (not a valve). One hose from the fitting goes to the deck pump out and the other to the macerator. Once you install the macerator pump and connect the hose from it to the through hull valve and connect the power source you should be good to go as long as the valve is not frozen. If it is, come back for further instructions.
A couple of tips. The macerator pump only works with the deck pump out cap secured. Otherwise, it just sucks I air and it will not prime. Also, if I use the pump during a cruise, when I return I always rinse the pump with fresh water by filling the tank with fresh water (after first pumping out the black water), then run the pump with the valve open for a few seconds to clear out any black water residue, close the valve and finish pumping out the tank. When the tank is empty, I continue to pump out while squirting fresh water through the tank vent until the pump out water becomes clear. By doing this, our system remains trouble free after many years of cruising PNW waters.