Not sure about the map sensor wire, but as for the tach wire....on my '86 their's 2 beige wires with brown connectors near the distributor. One is for the tach, and the other we could never figure out what it was for. I was told that it may be for diagnostic purposes that the normal person would never need. See if you have both identical wires. If you find another just like the one you have for the tach, plug that one in. My tach did not work when I bought the car, but once I found the "other" wire and plug it in it worked.
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