What type of bulbs do a Crown Victoria head lamps use?

A great source for this information is a website for a lamp manufacturer. I checked www.sylvania.com/ConsumerProducts where I found a very handy lookup tool. For example, for my 2004 Crown Victoria, the combined single low-beam and high-beam lamp is 9007 and Sylvania offers several different varieties -- long life, SilverStar, Cool Blue, etc. Chances are the original equipment was the lowest-price 9007 you'd find in any parts store. (Any manufacturer who makes automotive lamps will make one labeled as 9007.) Crown Victorias have been made for a long time, since they were Ford's replacement for their former flagship LTD model which followed the Galaxie line-up. Before the Galaxie showed up in 1960, Crown Victoria was a special trim level on Ford's basic full size models. At that time, about 1955 to 1959, full size Fords used relatively generic (for the time) sealed-beam lamps. I am assuming you could also check a manufacturer's website for modern-day equivalents if you had one of these original-series Crown Victorias. In the late '50s, many car makers were making the transition from 6-volt to 12-volt systems. If your vehicle was a 6-volt model, it may have been modified or modernized to accommodate 12-volt lighting.