id second the notion to place it under seat or somewhere else if up front if possible. i think if mounted and angled right, theres room up under where your feet are, maybe if you want to get tricky and wouldnt mind the cutting, you could midify your glove box somehow, though without cutting that would probably muffle waaaay to much sound. under seat or at the feet sounds good.
even if you dont want it to boom, go up front for good imaging
