Dave,
Thanks for the description and pictures of your battery compartment. On mine the pushrods were in the way to put a compartment in that location. I ended up making a compartment about half way between the wing opening and the subfin. It as accessed from the wing opening. Thanks again for posting pictures of your compartment.
I hope mine flies as good as yours. I will post a picture and a description of mine when I get it finished.

Jim