Milford, MI
just to clear thing up... from IPDB.org
Users have commented that they have seen more examples of 'Surf Champ' back in the 1970s (and subsequently) than one would expect to have seen for a game with a production run quantity of 1,071 units. While this quantity has been confirmed with data provided by Gottlieb, it is a relatively low number when compared to quantities made of Gottlieb's other 4-player games of 1976. That alone does not prove anything, but serial numbers of 'Surf Champ' compiled by users indicate a quantity of over 4,000 units were actually made. From this, it would appear that a typographical or recording error occurred in the Gottlieb data.
