You didn't have to run a parallel configuration for the 8 ohm amp requirement? I ask as I have an 04 Land Cruiser which is similar to your setup.I just replaced the factory sub in my 2006 with a Skar 6.5" dual 4 ohm that seems to be a good match for the factory amp, that required very little modification to the enclosure. The holes lined up with the factory holes (I needed longer screws), the only mod to the enclosure was removing ribbing in the inside back where the magnet was touching, and there's a little rectangle of foam on the panel right above the grill that needs to have some of it ripped off, or the panel would bulge slightly. on my rig green and yellow were positive, I used both sets of wires. the 5 little gaps around the new sub needed to be sealed for it to sound right. of course this was much easier with the disassembly instructions from the OP.
link to the sub I used (I used the 4 ohm) EVL-65 | 6.5" 400 Watt Max Power Car Subwoofer
and yeah I know i installed the sub upside down. At least I can't see it.
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