Thanks for your reply. It didn't work. For whatever reason, I couldn't get the class: td:bx-def-padding-sec-bottom.bx-def-padding-sec-top to work. Maybe because it is used by all the tds in the same table row.

Instead, I used the css class: td:nth-of-type(3) to apply the code to the third cell (td) of the row and it worked. Also I used the .html() element instead of the .text() element. Here is the final code:

<script>
$(document).ready(function() {
  $('#bx_acl_view_row_6 > td:nth-of-type(3)').html('<a href="./contact">Contact us</a>');  
});
</script>  

I could have used the .replaceWith() or .text() element, It would have worked as well. eg:

$('#bx_acl_view_row_6 > td:nth-of-type(3)').text('Contact us');

Thanks