The 1948 Cadillacs had small, round parking lights set in the center of a rectangular fog light housing (see above), on a horizontal plane level with the space between the 2nd and 4th grille bars (counting from the top).
This 1948 Cadillac Ambulance clearly served duty for the US Army's very top secret USASCC (U.S. Army Strategic Communications Command - part of STRATCOM) for the Vietnam War effort in and around 1972, best guess is at Fort Huachuca, AZ (as identified by a faded parking pass sticker on the front bumper).
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