well i don't suggest it because it'll most likely throw the balance off a little. but if you were to just add weights to the bottom to compensate for the mic on top, it would be funky because you'd be overloading on the top, and even though you evened it out on the bottom, it wouldn't work perfectly because it would be over the weight limit.
the mic on the bottom thing was only a suggestion if he wanted a project to toy around with