tmas-
According to your owner's manual, your coach is equipped with a standard 7-pin hitch connector. In addition to the drawing in the manual, see "7-Way Traditional"
at this link for which signals show up where.
On a standard connector, the stop and turn signals ride on the same wires (yellow is left stop/turn and green is right stop/turn). This is exactly what you need for your Jeep. You do not need a combiner. The Roadmaster diagram below is the one that applies to your situation.
Linear Mode
