I am glad you mentioned the charge controller location. The unit did not come with any instructions to speak of and the last thing I read on installing them was to put the charge contoler as close as possible to the batteries.
After you questioned the location I did some more research.
Next you'll want to determine the location for the charge controller. The charge controller should be as close to the batteries as possible but not in the battery compartment. Battery gases can corrode and over time destroy the electrical circuits in most solar charge controllers
There are a couple of reasons not
to have the charger in the battery compartment one is outgassing from charging, and rge second is corrosion I guess. So I will move it. I was not worried about out gassing so much because holes to ventilate have gone in.
Controllers also do not like heat or water, so I will figger a new location as close to the controller as possible.
I ended up riveting the cupboards in. To be frank I was too scared to glue them in. As it was I had to take the top cupboard out and put it back in a second time so I could get the backsplash in properly.
There are too many things that can go sideways and my experience is too limited which means that It is not a good idea for me to anything as permament as the kind of glue we are talking about
Anyway thanks for the tip on the controller. How did your cupboards work out did you go with the glue