Assumption : stock look using factory speakers location.
Equipment
Headunit: Alpine 7918R + Alpine 5957 cd shuffle + Alpine ERE G180 13-band equalizer
Front speakers: Midbass Hertz HV 165L + Tweeters Hertz HT 25
Rear speakers: Woofers Hertz ECX 690
Amplifier: STEG 75.6 mx
Speakers and amplifier "made in Italy"

For the first I suggest to soundproof front doors.


Enlarge tweeters holes a bit and fit new speakers in it.

6x9 speaker mounted on mdf distances.


1.5 din Alpine set.


I will try to fit it into a factory hole with working flap of course

Steg 75x6 (every speaker has its own channel and every channel has a crossover)

Front midbas cut 50Hz-1.8kHz
Tweeters cut 1.8kHz--
Rear work as woofers and are cutted --200Hz.
Effect is amazing. Pure analog sound with deep quick bass and clear vocal. Without any alarming noises.
I will paste some more after finishing all the job.