Unfortunately, I was busy for most of the day and was still pretty sick. Now I have a cold and a major headache, so I wasn't able to get any modeling today.
I was able to finalize the audio design, component-wise. It will have 4 internal speakers: (1) Front charge panel, (2) Rear side vents, (1) Neck/Body joint opening. It will be powered by a 12V 200W MOSFET amplifier which I just ordered tonight. Frequency-wise, the speakers are capable of 130Hz-20kHz. Because of that, I was thinking of adding a small woofer but price-wise, only a 70Hz woofer was available. I ran a high and low pass filter to see how the audio would sound and it didn't too bad or noticeable. So, unless it sounds really bad when I use the real speakers, I'll just stick to the 4 full range speakers for now.