Solar panel connection to chassis battery

[Nomore9-5]

This concerns a Georgetown but I think it might be the same for other motorhomes as well.
I bought a small 6 watt solar kit to keep my chassis battery charged over the winter( no power where it's stored ). The kit has two battery connection options a set of battery clips as well as a 12dc plug .Since I want to have the panel inside facing out through the windshield and there's a 12 v outlet close to the radio on the dash it would make life easy if I went the dc plug route however I have a concern
Unlike a regular vehicle that comes completely assembled the mh starts out as a Ford stripped chassis and Forest River goes from there. So here's my question - is the 12v outlet part of the Ford electrical system ( and therefore connected to the chassis battery) or is it part of the Forest River system and connected to the coach batteries.
I'm inclined to think it's the former since in the passenger compartment fuse panel ( Ford Owners Guide )there's a fuse ( 16 ) for a radio feed as well as one ( 5 ) for accessory feed but I'd like be sure I'm charging the right battery and not messing up all or part of the unit's electrical systems
Can you guys tell me which it is or if you've actually installed a solar panel like this for the chassis battery using the dc plug/ outlet on the dash.

[TitanMike]

Simple test. Turn off House Batteries by disconnecting ground. This will make sure they are ABSOLUTELY out of the picture. Now check outlet for power. If none, turn on ignition switch and check again. Often power outlets are connected through the ignition and if it is now live, it's connected to the chassis starting battery. If still no power then it's connected to the house batteries.

You may have to run a second wire from house batteries only to where you need the outlet if it's live on the second part of the test (ign on).

[Nomore9-5]

Originally Posted by TitanMike

Simple test. Turn off House Batteries by disconnecting ground. This will make sure they are ABSOLUTELY out of the picture. Now check outlet for power. If none, turn on ignition switch and check again. Often power outlets are connected through the ignition and if it is now live, it's connected to the chassis starting battery. If still no power then it's connected to the house batteries.

You may have to run a second wire from house batteries only to where you need the outlet if it's live on the second part of the test (ign on).

Mike - Sounds like a good approach. A lot easier than pulling suspected fuses under the dash which is a real pain in the _____. I might also just go ahead and find a way to route cable directly to the battery and be done with it. Thanks for the help