source: The Republican (Danville, Indiana) - issue of Thursday, December 8, 1960 - page 1, columns 6-7:
According to a newspaper article, in December 1960 the Hendricks County Commissioners passed an ordinance designating US 36 as "Main Street" throughout Danville. Washington Street in Danville was to be the crossroads for US 36 - all of US 36 to the west of Washington Street was to be known as "West Main Street"; all of US 36 to the east of Washington Street was to be known as "East Main Street."
The ordinance also directed the postal service to use a numbering system for houses along US 36/Main Street. The numbering system would start with the number 1000 and each one-mile section would be another 1000 consecutively. Addresses on the north side of US 36 would have even numbers.