How old school do you want to go?
Pioneer TP-900 8-track with a Clarion 300-EQB and Jensen Triaxials (mid 70's)
Killer system in the late 70's Alpine 7307 Cassette Deck, Alpine 3011 Mini-Eq w/3001 Digital Time Delay unit, connected to two Alpine 3002 50W + 50W power amps with Cerwin Vega CS-15's coaxial 6x9's with 8lb magnets or JBL T545's.
Pioneer Component systems KEX-20, KEX-50, KEX-65, CD-5, CD-7, GM-120.
Kenwood Hybrid KRC-999II with a KAC-1020, KAC-920.
Or
Nakamichi 350 portable cassette deck with a Fosgate (long before Rockford) PR-250, 250II, PR-2100, PR-2100 Type II or the A/D/S Powerplate 100 with A/D/S L200's or L300's.
Also a company called Car-Fi made an incredible high quality amplifier (big heavy monster) and matching equalizer that is rare as hell.
Magnum Professionals made some of the nice speakers around in the early to mid 80's. All cast aluminum construction even the grills and mid/tweeter modules. I found a pair of NOS ones on
eBay a few
Fast forward to the early 90's. Alpine 7909 or 7907 for a deck, lots of stellar high quality amps in the 90's with the best coming out around '95' - '98. Too many to list.
Check out my avatar it is an Orion GSX-300 less than 9 were ever made worldwide, triple 24kt gold plated, hand built and tuned by the Chief Engineer at Orion.
Some of the best of the best amps were the Orion XTR 100, XTR 200, NT 100, NT 200. Soundstream 5.0, 10.0 and Picasso are but a few.
I have been in Car Audio for decades. Moldy Oldie.