Well this is what the stereo needed.
Just finished fitting the new double DIN headunit. Still using the stock amp for the door speakers, but added a monoblock amp and 12" sub in the back. This used to be the sub woofer in the lounge room, but that amp packed it in so figured I should reuse the speaker here. It only barely squeezes in for depth inside the wheel. Obviously the spare has been flipped. It is still bolted down. I just cut down the tie bolt, and machined a bit off the handle.
New 6x9's in the front, but now really need to replace the rear door speakers with something better. They are letting the system down big time. Might start the search for some better dash tweeters when I get to it also.