drop down value

I have been looking through the forums and haven't been able to find exactly what I am looking for...but I believe it is possible with some jquery and a little know-how (of which i dont have any right now). I am trying to get the info from a selected drop down to changed the data in the form, while the user is still on the form. I can do some of this with conditional logic, but the list I have is very large and subject to change which would mean a lot of conditions that would need to then be adjusted....basically: Get the selected drop down and have that choice display somewhere else on the form while the user is still filling the form out.

Ideally:
I have a drop down menu which is populated from a taxonomy. I would like to access the "Label" when the menu item is selected, I would also like to be able to access the "Value" of the selected menu item--by access these I mean insert them into the form at different spots.

Scenario:
50 Items.
Each item will have 1-4 as a value.
your filter = {drop_down_label:57}
Each item name (label) will correspond to an image.
/img_{drop_down_label:1}.png

I found a couple of other posts that did similar things to this (at least to grabbing the label) but they weren't quite accomplishing the same thing.

ok. I am making progress on this. my error was that I specified the form _4 but then did not specify the form on the input

add_filter("gform_pre_render_4", "monitor_dropdown");
function monitor_dropdown($form){

?>
    <script type="text/javascript">
    jQuery(document).ready(function(){

        jQuery('#input_4_40').bind('change', function()
        {
            //get selected value from drop down;
            var selectedValue = jQuery("#input_4_40").val();

            //populate a text field with the selected drop down value
            jQuery("#input_4_61").val(selectedValue);
        });
    });
    </script>
<?php

return $form;
}