we convertible guys cant put those sub enclosures in the back like you can in the coupe. can't block the cargo shade.
I haven't messed with it but im sure you can stick a better speaker in there and toss in a better amp as well.
2013 ZL1 Vert
1990 IROC-Z Vert
2008 TBSS (for sale)
2014 Sierra Denali (ordered)