If you want to replace the door speakers in your second generation Scion xB (and most likely xD and tC) you have a few options. You can either buy a plastic mount and wiring harness. You can make your own mount out of new material such as plywood and just solder the wires. Or you can do what I did which is gut the old speakers and use them.
I have a full walk through of my speaker upgrade on my personal site but this instructable only covers how I converted the stock speakers into mounts. I just didn't think I should spend another $30 bucks on adapters when I can use the existing speakers that otherwise had no real value or use.
Step 1: Unsolder the Copper Leads
This part is really easy. Just flip the speakers over and use your soldering gun to disconnect the copper leads from the wiring harness in the speaker body.
Step 2: Pry the Plastic Ring Off the Top of the Speaker Body
As I looked at the speaker I could see that the speaker cone appeared to be glued to the body and retained by a plastic ring. Turns out the glue used to hold this thing together is mush weaker than I thought. I originally thought I'd have to heat it up but that proved to be unnecessary. Plus the sub level the ring sits on is hollow so all you have to do is notch a hole in the ring and then get under it and pry (see pic 1 and 2). Just keep prying all the way around and you’ll end up like the third pic a lot easier than you expected.
Step 3: Disembowel It and Carve It Up
Oddly enough I had a mentally hard time doing this part. It's just not normally in my nature to break working things. However once you get over it all you do is rip out the black woofer cone (you might need a razor blade to separate it from the yellow mesh).
Once you have that out then the next step is to take a dremel cutting wheel and just cut the supports. They don't have to be super smooth or pretty so don't worry about that part to much.
Step 4: Clean Up the Speaker Mount Body
Now we need to clean up our mess so we have a platform for the new speakers. You can see me using a chisel and a box cutter to clean up the mess left behind (there’s like some paper layer). Take some time to make sure this platform is all nice and clean and free of the old glue and gook.
Step 5: Mount Speaker to the Old Speaker Body and Wire It Up
Then all you do is take your speaker and drop it in the base you just gutted. Drill 4 holes that are of a smaller diameter than your screws and bob’s your uncle. It’s deceptively simple honestly…although I have to admit I would have liked the screws to be a little longer but they seemed to grip enough to make me happy.
In the last picture you can see the old speaker body with the new speaker in it mounted to my drivers side door. Since Scion (Toyota) decided to use rivets to hold the original speaker I ended up using bolts and thread-lock to put it back in (full details in my walk-through). As you can see though in the end we were able to reuse the original mount and don't have to mess with any type of wiring harness adapters.
Jimichan made it!