function change_car()
   {
      var i;

      document.getElementById("tc_tops").innerHTML = " ";
      document.getElementById("tc_colors").innerHTML = " ";
      document.getElementById("tc_products").innerHTML = " ";
      document.getElementById("tc_submit").innerHTML = " ";

      if (document.selector.car.options.selectedIndex != 0)
      {
         document.getElementById("tc_tops").innerHTML = "<select name=\"top\" onchange=\"change_top();\"></select>";
         document.selector.top.options[0] = new Option("Select Top", -1);
         for (i = 0; i < tops.length; i++)
         {
            if (tops[i].car_id.indexOf(document.selector.car.options[document.selector.car.options.selectedIndex].value) != -1)
            {
               document.selector.top.options[document.selector.top.length] = new Option(tops[i].description,tops[i].id);
            }
         }
      }
   }


   function change_top()
   {
      var i;

      document.getElementById("tc_colors").innerHTML = "&nbsp;";
      document.getElementById("tc_products").innerHTML = "&nbsp;";
      document.getElementById("tc_submit").innerHTML = "&nbsp;";

      if (document.selector.top.options.selectedIndex != 0)
      {
         document.getElementById("tc_colors").innerHTML = "<select name=\"color\" onchange=\"change_color();\"></select>";
         document.selector.color.options[0] = new Option("Select Color",-1);
         for (i = 0; i < colors.length; i++)
         {
            if (colors[i].car_id.indexOf(document.selector.car.options[document.selector.car.options.selectedIndex].value) != -1)
            {
               document.selector.color.options[document.selector.color.length] = new Option(colors[i].description,colors[i].id);
            }
         }
      }
   }

   function change_color()
   {
      var i;

      document.getElementById("tc_products").innerHTML = "&nbsp;";
      document.getElementById("tc_submit").innerHTML = "&nbsp;";

      if (document.selector.color.options.selectedIndex != 0)
      {
         document.getElementById("tc_products").innerHTML = "<select name=\"product\" onchange=\"change_product();\"></select>";
         document.selector.product.options[0] = new Option("Select Product",-1);
         for (i = 0; i < products.length; i++)
         {
            if (products[i].car_id.indexOf(document.selector.car.options[document.selector.car.options.selectedIndex].value) != -1 && products[i].top_id.indexOf(document.selector.top.options[document.selector.top.options.selectedIndex].value) != -1)
            {
               document.selector.product.options[document.selector.product.length] = new Option(products[i].description,products[i].id);
            }
         }
      }
   }

   function change_product()
   {

      document.getElementById("tc_submit").innerHTML = "&nbsp;";

      if (document.selector.color.options.selectedIndex != 0)
      {
         document.getElementById("tc_submit").innerHTML = "<input type=\"submit\" name=\"submit\" value=\"Go\">";
         document.selector.product.options[0] = new Option("Select Product",-1);
      }
   }