You can get the molex-type plugs out. I have run 12 Ga cable into my doors. Honestly it's more trouble than it is worth, and if you don't have small hands it's a real PITA. Once I had the passenger door done, I couldn't stop And had to do the other door. Needless to say my rear doors are using existing wire. My buddy Kyle's truck is using existing wire with no issues. Unless you are trying to push an ungodly amount of power into those door speakers, existing wire is fine. I have 8-inch drivers as part of a three-way system in the doors and wanted to ensure I had clean cable going in there.
First and foremost, diconnect the negative terminal on your battery and wrap it in a towel or plastic so there is no way to connect to anything....I am overly safe.
If you look in the door jam at the boot, push down on the top of the boot and away from the truck and the boot will open up exposing the molex. There is a majenta handle on it that when pulled on will disconnect the molex. You have two options from there. Drill out the inner and outer molex plugs where there are no connections making sure that the holes are drilled perfectly clean. This has to be perfect because if not, the plugs will not connect back together properly and lock. The second option is to cut the inner and outer plugs and solder your own wires in place circumventing the molex. Option two sounds difficult, but it's really not, it's just time consuming and a PITA because wire colors are duplicated. Also in option two you will have to dremel out the inner molex and route it back into place in order to reattach the boot. I know this because I had to take the time and do option two, and I will never do that again. I put a lot of time and detail into getting it right and it's way more than needs to be done. Like I said, once I got one door done, I kinda had to get the opposite door done to be symmetrical. My rear doors only have 6.5's so I am using existing wiring.
Honestly, as I have learned, anything more than the factory wiring is overkill.
To tap the factory wiring after the Bose amp, just expose some of the wire and solder in an attaching wire from your own amp. Make sure to unplug that wire from the Bose amp though. Be careful when playing around that bose amp, disconnecting all the plugs can really screw with it. The Bose amp requires a load on it in order to work correctly and it has been documented that some people have tapped it in such a way as to zero it out because the amp no longer seen a load enough for it to actually turn on. The easiest way to tell is if your 8-inch screen acts as if it is on but with a black screen....reverse camera still works.
If you need some help, I am here, just PM me or post on my build and I will get a notice.
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