i have a 1st gen Gs300 with nakamichi system and i just got an eclipse 7301 headunit for it. I'm gonna get it installed but i wanted to ask you guys a few Qs before the shop rips me off. First question is this head unit has a 1.5V preamp output voltage, which i don't really understand why because every other eclipse unit i've seen has at least 5V or 8V, so i was wondering if i should just get rid of this unit just because of that reason or can i still get decent sound out of it? another question is can i get it installed without having to replace the factory speakers, amp and sub? or would i have a better luck getting all aftermarket speakers, amp and sub? thanks