i was looking to upgrade my stock speakers in my 00 ws6. I already have a sony h/u ( suprisingly good ) and 2 10" memphis subs but am probably gonna get alpines soon. I was wondering if I should replace all speakers or just the door speakers or door and sail panels ? and if I replace just the door speakers can I run them to a 600 watt sony 4 channel amp (also suprisingly good). I am getting a Audiobahn DUB8001 800 Watt Amplifier for the subs ( new alpine typr r's)..any help would be greatly appreciated ...