Address data field not displayed on checkout

Hi all,

We have a small problem. We decided to divide the user street name address_street field to 2 fields, the street name -> (address_street) and the address_street2 -> as house number. We made the address_street2 core field also required, as the user must fill it in separately from the street name, because some of our customers forgot to add the house number also after the street name. The problem is, on the checkout page, the address_street2 field ( that was "Complement" originally) which contains the house number, does not appear,so that the user cannot check if it is correct or not, and also, it is not sent via the order notitfication mail sent for the webmaster, which is also important because the "packaging" colleauges dont have access to the hikashop backend, they only receive an email.
Another thing is that, in email and also on checkout page, just the name of street is displayed, but it would be much better in a format like this:
Street: somestreet (address_street)
Number: somenumber (address_street2)

How to solve this issue?

Thanks a lot.

Nice and flexible, we could solve it this way. Thanks for it!