new owner owner of '91 200

[o]

Hello, I'm new to the 200 world (and to this list, so I hope I'm sending
this correctly). I love the car so far, but I am in need of some info.
First, parts of my instrument cluster don't work right. The clock, the auto
check(?) system, and the computer that is supposed to give info like miles
to E are all inop. I have read these can go bad, but have a hard time
finding a step by step repair. TBH I would rather just replace it since I
don't think I could fix even with a guide. I guess the short version is,
where can I get new IC? Also, it currently it has some aftermarket cd
player that doesn't work, but I would like to find an original radio with
old school cassette. Are these difficult to find? because I haven't had any
luck yet. THANKS!