Look, I know we're Bonneville guys here, but I ran into this problem back in March, and posted on clubgp, but nobody replied. I guess first I should ask, do Bonnevilles come with the same Bose system that the Grand Prix has as an option? (My wife'* is a 2001 GP GT).
If so, I was considering keeping the factory head unit, but replacing the Bose amp and speakers with aftermarkets. Ideally I'd wire the new amp up to a factory-compatible wiring harness connector that would plug into the factory harness exactly as the Bose amp did, -but nobody makes an aftermarket harness for that connector. I suppose I'd have to get another Bose amp at a salvage yard just to chop the connector off it.
Even so, I question how the Bose system powers the front speakers. They are wired from the HU to the trunk amp, back up front to the doors. But are they really powered by the trunk amp, or do they just pass through the trunk amp unchanged?
-Nobody has been able to answer that.
I ask, because there are conflicting reports that the Bose Amp only drives the rear speakers, and that the HU provides the current driving amplification for the front speakers. But if that is so, I don't understand why they'd bother to route those wires back to the Bose Amp in the trunk, then back to the speakers in front.
Also, I think there is an error in the wiring diagrams for the factory bose system:
The description for pin 11 on the HU says "Speaker Return -Left Front"; but the HU does not directly connect to any speakers, and there is no corresponding "black+white" wire on any of the speakers or the Bose Amp. This looks like an error to me.
Connector diagrams here:
97 SE, teflon wiper blades, Dunlop Sport A-2 tires, Leather steering wheel cover, Pioneer DEH-P480MP mp3 CDRW head unit, Pioneer 12-disc changer, iPod hookup, Boston Acoustic 3 way 6x9'*, Boston acoustic separates in door pods, Alpine 4 channel amp in trunk. Magnaflow dual outlet muffler and Ractive stainless tips. Autozone rice pipe and K&N 4750 intake kit. Clear corner lights. Energy Suspension end links.