Heirarchical Select menu only working on backend pages

I am building an automotive parts site and I want the user to be able to use the Heirarchical Select module to perform their search. The way I see it working is the user selects the year, a new drop down is created forcing the user to select a make of vehicle, and based on that selection they are forced to select the model. My problem is I can't figure out how create a Heirarchical Select menu for the user. I can only use HS on the backend pages as a widget type for a term reference.

Thanks,
Adam