The Blose has to go. Its one of the first things most Z'rs end up doing after they purchase an original equipped Z32. The 1ohm setup is gimmicky and expensive.
So, the simple answer. Yes, rewire the car. Run new speaker wire, run 2 external amps. 1 for mids/highs the other for a moderate subwoofer. Purchase the OEM Nissan speaker mounting brackets around $120 all together and toss in some nice componets. A truck box will accomodate a 10" or 12" subwoofer in the hatch and still leave room for TTop stowage.
A 400watt 4 channel amp and a 2 channel 200watt work pretty nicely. Coupled witha good headunit, you will not regret the money invested in the setup.
Bose=Blows If you go to TTNet and do a search there is alot of info regarding all this.
www.twinturbo.net