I also added code to 2 of the FEC files so the customers phone number will show under the addresses on the checkout page, I think this is important so the customer can confirm their address AND phone number before submitting the order, especially when using the one page checkout.

After installing the mod (carefully read the readme file first and manually merge code into your files), use this code below for FEC:

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FEC files mods. This will add the phone number to the bottom of the addresses shown on the checkout page
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* 1) FEC file /includes/modules/quick_checkout.php
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Find around line 440:
'entry_country_id' => $country);

Replace with:
'entry_country_id' => $country,
'entry_telephone' => $telephone);

Find around line 489:
array('fieldName'=>'entry_country_id', 'value'=>$country_shipping, 'type'=>'integer')

replace with:
array('fieldName'=>'entry_country_id', 'value'=>$country_shipping, 'type'=>'integer'),
array('fieldName'=>'entry_telephone', 'value'=>$telephone, 'type'=>'string')

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* 2) FEC file includes/modules/fec_create_account.php *
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Add to the end of line 489
'entry_telephone' => $telephone,
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