I want to add a separate amp and subwoofer. Any suggestions on something that takes very little space?

 

Found this. Awesome

https://www.clublexus.com/forums/is-...-overview.html

 

I'd search major audio companies and inquire with them about an upgrade...when my friend bought his BRZ (one of the first), I introduced him to the folks at JL Audio and they immediately made a deal to use his car as test fitment for a stealth box. With use of his vehicle, they installed amp, sub, stealth box and clean sweep with no costs to him.

was a win-win...car will be down maybe 1-2 weeks though and at their shop for build/testing