This was an interesting project that had a few iterations before it’s current state. Originally when the inventory database was imported, an XML file would be generated to fill in the select boxes, but it took up a good bit of time to write the file and drive space because it was enormous.
Now this works with a simple Coldfusion API that I created to return JSON to populate the dependent select boxes. Using the API with stored procedures saves tons of time and disc space. The interactive front-end was made with the power of JQuery. You can try it yourself at wrightcars.com