We have a 2017 Venetian so I'm not sure if the Solar return wires will be in the same bay. On the Venetian, the two wires terminate in the bay with the Inverter and they were wrapped by black electrical tape. I think the color was orange & white.
I added 2, 24v flex panels to the roof and held them down with eternabond tape. Used MC4 connectors and connected the two panels in parallel.
In the bay I installed a EPEVER 40A MPPT controller with a MT50 remote meter.
I ran wires from the controller direct to the house batteries.
Everything works great.
Hope this helps you.
Robert & Laura Hennessey
2017 Thor Venetian A40