Hey, clamb... great post!
I'm doing a 'vintage install' myself (geez... I guess we're getting old enough to use that word, huh?).
I've had a bunch of Soundstream and Audio Control gear in storage for over 20 years, and I unearthed it THIS year. It all works, so I'm putting it in the car! I had to buy a new head unit (now for that, I WOULD counsel you to 'go modern'), but I've tested everything and it sounds great.
BUT, you asked in the title if we could 'talk you out of it.' And the truth is... I'm not sure I would do it. I'm doing it now because I already have functioning equipment in hand. If I didn't, I probably wouldn't 'go old school.' Here's my thinking (take it for what it's worth):
(1) Foremost, I think it's going to be hard to find new equipment from that era. So, you'll be dealing with 'the previously owned.' That's not always a deal-breaker, but with equipment of that age, you'll probably be buying 'as-is.' For fun and leisure (I know... I should get a life), I've browsed eBay over the years looking at old school car audio, and I think that the quality you're looking for is the proverbial needle in the haystack.
(2) Let's say you find equipment you like from a reputable seller, and you feel good about the purchase because the electronics have been 'bench tested,' Even if that's true (and it might be), old capacitors and transistors can 'crap out' even after repair--sometimes weeks or months later. And one thing I can tell you DEFINITIVELY is that it's difficult to find anyone who can or will repair an 'old school amp' (one of my old amps DIDN'T work, and I tried every shop and technician I could find in the state and NO ONE cared to touch it--for any price!
(3) If you're looking for sound quality, the processing available with today's amps are a wet dream for a mid-90s audiophile: totally customizable crossovers (frequency/slope), time alignment, 30-band EQs... it's all built-in (if you get a good one with a DSP). To use your vintage stuff, you can get an external DSP, of course, but it's awfully nice to have that built into your amps.
Just saying 'Linear Power' and 'Cerwin Vega' queued up the nostalgia! I totally get the desire to 'relive the days' with that equipment, and I don't think it's silly at all what you're considering (although you'll get some die-hards who might say otherwise). But the challenges of finding decent equipment and having someone who can repair it if things don't work out... I would probably spend my money on a nice 6-channel DSP amp, some satellites, and call it a day!
Good luck!