Not sure how you electrical panels are configured. The Winn configuration on my coach is a 30 amp breaker feeding my Dimensions MSW inverter. There is a transfer switch in most RV inverters so the 30 amp feeds an Inverter panel where you should find the inverter circuits for your TV,etc. You effectively have 2 panels - the main one and a 30? Amp feed to the second panel for the inverter circuits.
Once you find the inverter panel - mine is beside the main breaker box, you can add a new circuit for the Res Fridge if there are spare slots for an additional breaker. You should make sure that your old fridge wasnt on the inverter already. My Norcold 1200 was connected to my inverter so I just used the outlet for the Samsung fridge.
If you can install an outlet and connect the wiring, it should not be too big a job to wire a new outlet. The tough part is routing and installing the cable run so if you can use an existing inverter outlet, your task will be simplified.
Good luck, you will ask yourself why you didnt install the res fridge years ago!
09 Journey 39Z