How to add links within the checkout_shipping

My checkout shipping looks like this, just changed some of the text. Apparently a lot of customers want more details or dont understand at all, so I am thinking to add a link, maybe after each descriptions, where they click and pop up a window with more details. Somewhere behind the 'Best Way'. a hover and pop up is excellent but I have no idea how to do that. The next best is a link, but need some help in the coding.

The lines involved are:
define('MODULE_SHIPPING_STOREPICKUP_TEXT_WAY', 'Walk In Self Collect') ;

how do I phrase the code? can the
<a href="index.php?main_page=xxx#abc"> structure work here?

Try this:

define('MODULE_SHIPPING_STOREPICKUP_TEXT_WAY', 'Walk In Self Collect - <a href="http://www.domain.com" rel="nofollow">added link description</a>');

Lovely. But this method will jump the page to the so called faq page. This might interfere with the checkout and lose some orders. So I will try to take it from here and do a click to open a pop up method. Will post once I am done.

Got it working. But got a problem

The page is:

http://www.onlineshop.com.sg/index.php?main_page=checkout_shipping

Need to log in to see it.

The code I used instead is :

define('MODULE_SHIPPING_FREEOPTIONS_TEXT_WAY', 'Free Shipping - <a href=http://www.mysite.com/index.php?main_page=shippinginfo#freeoptions target="_blank" toolbar="no" width="200" height=150">Details**</a>**');

It pops up a window and jumps to the correct 'anchor' for just a split second, once the sidebars load, the images cause the lines to jump and the final display is a few rows or paragraph down.

If I refresh the page, it will jump back to the correct anchor. Any way to solve this? In the first place, I want to remove all the sideboxes if possible. I only need the text.

An even bigger problem, now when customer checks out, click on next, they get:

Warning: Cannot modify header information - headers already sent by (output started at /home/onlinesh/public_html/includes/languages/english/modules/shipping/storepickup.php:40) in /home/onlinesh/public_html/includes/functions/functions_general.php on line 44

This it the line 44 code

header('Location: ' . $url);