Anyone know of a reputable/experienced company to perform an upgrade to my 2009 MCS?

I could do it, but probably would need surgery following the contortion usually associated with these upgrades (my body just doesn't move that way anymore)?

Want A-Pillar speakers, new speakers all-around and an amp upgrade while staying within the space limitations of the mini.

I live in Tullahoma TN. Going to MOTD this month. If there will be vender to speak to, I'd be interested.

I want it to sound great with plenty of volume and quality sound.

Any help is appreciated.