I just got invlolved in this recently, and there are several steps and considerations.
In my area, it is important to contact the local municipality and/or their engineering firm and obtain their specifications. They will be responsible for the maintenance of the street lights afterwards and they want to minimize required inventory.
The fixture head itself will have specific technical information pertaining to types of distribution and optics.
If your township street lighting ties into a PoCo URD system, you will need to submit an application for electric service with them.
[This message has been edited by Redsy (edited 12-23-2004).]