Dreaded aftermarket stereo question...

[MCNPathfinder]

Hey everyone, so I've just about had it. I have a 2001 Pathfinder LE, with like every option. Unfortunately, one of those options happens to be the Bose sound system. Right now I have an aftermarket deck installed (came like it from the dealer), but you have to turn this thing up to 55 out of 62 to get any reasonable volume out the main speakers, my subs are just having a blast though because they're getting the full 4 volts on the pre-outs and the gain is just barely bumped. Anyways, the way it was wired before they had it running through one of those "Premium Sound Line Output Converters" and you would turn it up to get some sound and it would be distorted because the head unit amp can't put that kind of power out without nearing distortion. So the distortion is coming from the head unit internal amp. So I change it up and wire some RCAs on the wiring harness and remove the Line Output Converter. I get no distortion now with the 4 volt pre-outs, but I just don't get loud enough volume. It's far too quiet! So I've decided I'm replacing all the Bose stuff. Easier said than done. How are all of you getting speaker wire into the door? There's so many freakin' wires that I can't even get my hand up in there. Anyone here changed out the factory nonsense and ran a new amp and wire? I'd love to hear how you did it because this is just crazy! By far the hardest install I've done and I've done it on 2 other sedans, I'm thinking that an SUV is supposed to have more room and it would be easier, but boy am I wrong! Lol!
Thanks in advance for the help!