Credit Card type on drop down

[somersm]

I need to put a drop down select for on my checkout_payment.php page but cant seem to find where to do it in the checkout_payment.php file

 

at the moment on processing my CC I cant select what credit card to use ie VISA or MASTERCARD I just want to add in a dummy user select box to add familiarity to the user

 

any there any sources on the forums for adding extra content to the forms

 

tks

martin