I had a plane that was really nose heavy. I mounted my battery pack on some balsa and glued into the fuse. I used the pack to get an approximate area for the balance. Then I cut the balsa so it would sit on two formers in the fuse. I put some epoxy on the balsa and put into the fuse, making sure the battery was in the area needed for the balance.

The bad thing is when I need to replace the battery; gonna be a mess. Good thing, no dead weight. Not the best way, just my way.

p.s. I can never find your guys field up that way. I usually windup flying at a school in Anacortes, just staying high above the trees.