Amend Greeting in Email Template

Please help,
We are trying to amend the email template 'Order creation notification'.

The Default Value is:
Hi Name,
<?php echo JText::sprintf('HI_CUSTOMER',@$data->customer->name);?>

We want to change this to:

Dear Mr Lastname,

We have amended the Language file and amended the template file in Hika shop admin to:
<?php echo JText::sprintf('HI_CUSTOMER',@$data->customer->title, @$data->customer->name);?>



Please can you advise me how to do this.

Regards,
Sean R.