Get (2) 5/8" rubber grommets and super glue them together. Then trim one lip as shown in pic. The dash is thick in this spot so a standard grommet isn't thick enough. When drilling hole in dash be aware that there is a wire loom that runs up over the area of the gauges. It will seem odd drilling such a large hole in your dash but this size grommet works well. Pull the wire first and slip grommet over wire. Work grommet into place.
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http://i523.photobucket.com/albums/w...cks2go/002.jpg
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