I knew I had these pictures dating back to year 2004 when a guy here on PY, helped me out when I fitted a power antenna into my 1966 Grand Prix. Just took ages to find them!
The critical part is the distance back from the forwardmost part of the trunk lid and the position in from the side of the trunk lid. Whether you own a Grand Prix, a Catalina or a Bonneville, all those measurements are the same.
Good luck and let us know how you go
Ian
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