I removed the rear deck speakers in my '91 Geo Prizm (same as corolla). Let me tell you it's not easy. This was a couple years ago but if I remember correctly you have to go from the top side of the speaker. First you have to remove the speaker grill, then I think there was some black papery stuff you have to rip out before you can see the screws. I actually had to file back the plastic molding a little to be able to get a screwdriver in there to remove a couple of the screws. Once you get those removed you should be able to wiggle the speaker out, but the worst part is, toyota/geo did not leave any slack in the speaker wires so you can't pull them out very far. What i did was just cut the speaker free and then solder some longer leads on there so installing the new speakers was easier. Hope this helps you somewhat. Sorry i didn't take any pics while i was doing it!
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