I was running my 12" JBL sub and just stock front speakers off a Sony headunit in the GT stripped and it sounded decent. When I get it on the road though I will be putting all the seats back in, some Vibe Slick 4" speakers in the front and will be using 2 amps, a 4 channel to power the Vibe fronts and JBL 6x9s in the shelf and the 2 channel one I have for the sub. It'll weight a fair bit I know, but the power will offset that anyway. (Was planning to do this in the NA but another amp, heavier front speakers and set of wiring and I wouldn't be able to put up with it!) I was driving the NA stripped with just the 6x9s in the back and it felt so much nippier, but I needed my bass lol