House battery question for Super C owners

[Dracula]

Hello All,
I have a 2017 Chateau 35SB. I think I have a dead house battery.
The RV is in storage about 5 miles from my house, but unfortunately I have very poor cell service there, so I'm looking for advice before I head over to the RV.
Just looking in through the top step in the entry way, I see no way of getting the batteries in and out. I have not laid under the RV yet to see if they come out that way, but I am pretty sure they do not come out through the top step.
Has anyone replaced the batteries themselves? If so, what is the best way to get the batteries in and out?

Thanks in advance!
Eric

[Edk]

Eric, I have replaced mine in the 2016 sk, they did come up through the step.
I latter added a 3rd battery, so ended up converting a compartment with a slide.
Now have 3 12v 155ah batteries.
Hope this helps
Edk

[Dracula]

Thank you Ed! I would have never guessed they would come up through that opening (just looking at it). I'll get back over to the RV in the next couple of days and test them. I believe one of them is dead.

I'll be there replacing my one year old water pump!!