I always find it odd to see someone i personally know on the same forum through happenstance.
Call it the Pi Piper.
Also, I don't know how your insides are set up, but you could probably fit a couple 14500 li-ion batteries in there if you have 4aaa (i'm assuming NiMH) batteries in there. Or a 14650 li-ion. Both options would give you less voltage, but be easy to remove. Both batteries are AA diameter and the 14500 is basically a AA with Li-ion. (14650 is a lil' longer...)
Also, Also- it took me a while to figure what the numbers mean for the batteries. the first two numbers (14) represent the diameter of the bat in mm, the second set of numbers is length in mm (50mm or 65mm). The length is only approximate, though, as the nipple on the positive side of the batteries can add a mm or two. Correct me if I'm wrong, here, Oh More-Experienced-Than-I users!