I'd say keep it but do the hidden Bluetooth audio thing.
I'm a huge fan of vintage audio and stereo equipment. I actually have a 90's vintage Blaupunkt Mini Disc player that is being saved for my 914. Remember Mini Discs? Of course you don't. They never caught on and were quickly replaced MP3 players. Much the same 8 tracks never survived by being pushed out by cheaper and more reliable cassette mechanisms.
A note of warning for 8 Tracks - They have rubber pinch rollers (inside the 8 track cartridge that get brittle as lead to slippage and player itself will have rubber drive belts. Belts often get brittle and break or sometimes the rubber turns to goo if it's already been slipping. The problems above are for home units, things will only be worse for automobile units.
If you intend to ever use as a 8 track - it will likely need service 1st to be usable after sitting for years in a hot car.
Parts are available (for both cartridges and players) and there is a cult of 8 track users - just like there is a cult of 914 owners.
Now your a member of two cults.
http://www.8trackheaven.com/archive/work.html