calling filters via ajax

I’ve created my WP ajax following the codex: http://codex.wordpress.org/AJAX_in_Plugins. I am trying to call specific filters based on user’s interaction with my admin section. Unfortunately, I haven’t been able to turn up anything on here or google about using ajax like this. Basically, when a user clicks a button, I need to set some filters to restrict upload types, among other things for the Media Upload box (Thickbox, ie tb_show()). What I have done so far is:

click function:

jQuery.post(
   ajaxurl,
   {action:'handlePDFUpload',
    ajaxNonce:hsciAjax.ajaxNonce},
   success: function() {
      tb_show('Please Select Your Completed Work Plan PDF', 'media-upload.php?type=file&TB_iframe=true&file=xxx&page=xxx');
   }
);

(return false to stop form submission)

And the action handlePDF

add_action( 'wp_ajax_handlePDFUpload', 'handlePDFUpload' );
function handlePDFUpload() {
	add_filter('media_upload_tabs', 'remove_media_library_tab');
	$response = json_encode(array('success' => true));
	header("Content-Type: application/json");
	echo $response;
	exit;
}

Removed nonce stuff so I don’t exceed the code guidelines.

Once this is handled, I would use the tb_close or tb_remove function to remove the filters at hand. The reason for this is I have 3 different upload button in which I need the users to upload very specific files. However, the filters are completely ignored when clicked. Any help would be greatly appreciated.