Why you don’t create new sidebar called “Top category”
Goto wp-content/themes/your_theme/
1/ Open functions.php and paste this code
register_sidebar( array(
'name' => __( 'Top Category', 'default' ),
'before_widget' => '',
'after_widget' => "",
'before_title' => '<h3 class="widget-title">',
'after_title' => '</h3>',
) );
2/ Open category files (usually it is archive.php) and goto the place you want to show this widget and paste this code
<?php if ( ! dynamic_sidebar( 'Top Category' ) ) : ?>
<?php endif;?>
3/ Goto Widget and drag widget “jcarousel-post-slider” to Top Category.
Done!