picture image for join and login dv6.1.6

Im wanting to change the login and join top right so they are pictures that i have drawn up instead.

Would anyone know what php file this would be in, or where they might be if not.??

thx.

You can find the login and register in the language file. 
search for member login and Join now  then change that to the image path and url to join.php or member.php

If This is where you looking for.

thx for the info great, worked like a charm.

Also added this below in function.php and dropped in the join and login jpgs in "templates/tmpl_uni/images."

After line 210 u will find the login and join block.

<a href="<?= $site['url'] ?>join.php"><img src="templates/tmpl_uni/images/join.jpg" title="JOIN NOW"/></a>
<a href="<?= $site['url'] ?>member.php"><img src="templates/tmpl_uni/images/login.jpg" title="LOGIN HERE"/></a>