I hang out with the stereo guys on AudioKarma as well, the gravy days were 10-20 years ago, the good stuff was sold for dirt cheap. Now anything that can be cleaned up and look OK is saleable. Most of my last big purchases needed repairs (and I knew it). It is odd that the engineers don't hang out in the forums, I posted the AIWA guys newer website, a few guys have popped up over the years on other forums but they never stay long. There was going to be the huge documentary "Boombox Creators" but it fizzled out with no reason posted.
Toshiba RT-S90 I have two of them This one the cassette works but there's just no sound in the cassette and I had to reflow the upper circuit board to get sound from the radio but I can't get the cassette to give any sound.
That's the kind of big nasty complex boombox I would not want to work on Good luck with that one James! Yikes.