I have seen the very common failures on 124's for a long time. The wiring harness should be covered by the dealer up to about 100k miles.
The other things are minor cost wise and should be done soon.
PS if your dealer heres you scream you have a better chance of a free harness. I know they have replaced about 100million of the engine harnesses here in Atlanta.
1991 GMC Syclone
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