High end car system

I am building a system for my car to be as good as I know how with my experience from home and past car stereo competitions in iasca. I have been working on it for about 2 months and installing everything myself. I wish I could post my photo progress for comments and discussion. 
Have you experimented with placement of
SR HFTs and Bybee QSEs in your car?
There are posts on applications of these units in cars.

You may start, modestly, with one HFT on your windshield,
a few inches under the base of your rear view mirror.
I have a QSE suspended by a 6" piece of wide, clear tape.
This way, the piece covers the radio but does not interfere
with cd insertion/removal.  The top of the tape secures it
to the dash.

I also use a Walker Talisman around the face of the radio and
the speakers, and the cd, too.

See if these can make a difference for you.
I think you're spinning your wheels.   I have a very high end system in my car made by Burmeister.  It sounds real good only at traffic lights....as soon as I drive off the engine/tire noise swamps whatever delicacy, high end sound it had at the light. 
Battery power. Pneumatic and spring isolation. No crossovers. That’s a good start. 🤗