$tld_wcdpue_email_variables = array( "{account_url}", "{account_url_trim}", "{product_name}", "{product_url}", "{product_url_trim}", "{first_name}", "{last_name}", "{download_url}", "{download_url_trim}" );

//Write your replacement variables in the order of your magic tags
$tld_wcdpue_email_variables_replace = array( $tld_wcdpue_account_url, $tld_wcdpue_account_url_trim, $tld_wcdpue_product_name, $tld_wcdpue_product_url, $tld_wcdpue_product_url_trim, $tld_wcdpue_customer_fname, $tld_wcdpue_customer_lname, $tld_wcdpue_download_url, $tld_wcdpue_download_url_trim );

$tld_wcdpue_email_body = str_replace( $tld_wcdpue_email_variables, $tld_wcdpue_email_variables_replace, $tld_wcdpue_email_body );