Good info here.
2001 Toyota Sequoia - SR5 with JBL Stereo.
My build is as follows: 2 Din Headunit, cheaped out on Pre-outs and bought a cheaper Unit (only 1 - Pre-out, this will not allow me to control system through head unit. But I will be able to adjust sub/speakers, with the amp gains and sub adjustment dial amp comes with.
I have not added speaker adaptors, wiring, Sound Dampening, or capacitor for build, to this list. As I complete I will take pictures. If you have a question, just post I will do my best to check in.
For Front Lower & Tweeter: Powered by amp
https://www.hertzaudiovideo.com/car-audio-speakers-system-mille-pro-mpk165-3/
Front 2 inch Mid: Powered by head unit.
https://www.massiveaudio.com/products/mx2-coaxial-speaker
Rear Lower: Powered by amp
https://www.hertzaudiovideo.com/car-audio-coaxials-mille-pro-mpx165-3/
Sub: Rear Driver side Panel - I haven't decided what sub to use or if I will make my own enclosure. Link is example of what is available.
https://www.crutchfield.com/p_13694109/JL-Audio-Stealthbox.html
Amplifier: This will power the front component set, Rear Coax Speakers, and rear Sub.
https://www.hertzaudiovideo.com/car-audio-amplifiers-mlpower5/
This is a 4 ohm system. I looked at a bunch of 2 ohm systems but in the end this was a great deal for me, as I bought all the main items on sale for around 50% off. It also doesn't matter except in the power output from the aftermarket amp. I will not be using the stock Toyota JBL amps. I will re-wire the doors with higher grade wiring to each set. Since I am wiring the doors anyways from the amp, the amp bypass wiring kit is not necessary.