Display new field (previosly added on customer sign up) on customer address book

My case is very similar to that discussed in this post (now closed):
http://www.zen-cart.com/forum/showthread.php?t=68000
But I do not find solutions.

I have installed 1.3.8 version of Zen Cart.

I managed to successfully install the module "Extra Field on Customer Sign Up" available from the following link:
http://www.zen-cart.com/index.php?ma...oducts_id=1694

So far, so good.

The new changes to the database are:
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ALTER TABLE customers ADD customers_extrafield varchar (32) NOT NULL AFTER customers_fax;

INSERT INTO configuration (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, set_function, DATE_ADD) VALUES ('Display Extra Field', 'DISPLAY_EXTRAFIELD', 'true', 'Display "Extra Field" on account creation page', '5 ', '6', 'zen_cfg_select_option (array (\' true \ ', \' false \ '),', now ());

INSERT INTO configuration (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, set_function, DATE_ADD) VALUES ('Require Extra Field', 'EXTRAFIELD_REQUIRED', 'true', 'Require Extra Field in the account creation', '5 ', '7 ',' zen_cfg_select_option (array (\ 'true \', \ 'false \'), ', now ());
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Everything works properly.

But like the user esugrue (Ernie) I need that this new field appears along with the rest of fields that make up the user's address/es:
company, firtsname, lastname, street address, suburb, postcode, city, state and the NEW FIELD CONTENT.

For in this way may appear also included in the shipping and billing addresses of invoices and packing slips of Super Orders 3 module.

My question is this:
What files should I edit to get what I want?

Thank you in advance.
Greetings.