I had a similar issue with my 81. I used a B+M shifter and a column from a floor shift car installed into a car that was originally a column shift.
I bought a park/neutral relay from Painless to solve the issue. Wires go right to the micro switch and tie in with the purple wire/starter connection. Easy after I found out how to do it.
Got a lot of info here on the forum.
The tangs on the switches needed some tweaking but thats done. Not sure how your shifter is set up compared to mine though.
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