'70 Dart: Deluxe Seatbelt Package?

Hello, I have a '70 Dart, and in the owners manual, it states that there was an optional "Deluxe Seat Belt Package" that consists of more color choices for seat belts, storage brackets, and a seat belt warning light. Question, where does this "seat belt warning light" mount?

I found that YearOne makes a reproduction of the warning light, but it is for 1971 and later models (part # BK56). As part of my research, I had to obtain a manual for a 1971 Dart/Demon, and NO mention at all of any deluxe seat belt package in that year.

So where would/should I mount the seat belt warning light? I need this to be as accurate as possible. If anyone has any pics of this seat belt warning light for 1970, please let us know. Also, what production code would this be? I could not find any mention of a production code for this deluxe seat belt package.

Thanks