I managed to stick two bits of velcro down towards the rear of my plane by using tweezers through the servo area. This worked fine but I stupidly only used rubberbands to attach the batter to the anti-vibration foam that was then stuck to the velcro strips. The battery slipped out, luckily it happened on after a landing. I have now used a tie-wrap to attach the battery to the foam. In the end though I just cut a big ugly hole in the side of my plane. If I ever need to get at the battery I will have to cut another hole in the side of my plane.

Without having the battery as far back as possible I just found the plane to be way too nose heavy. It is still nose heavy with the battery near the back, but the situation seems to be manageable.