Validate a new credit card

I need to know how to add a new credit card to the validation for the manual credit card module. It is accually a gift card but is processed through my credit card terminal. The card is 16 digits, does not have a expiration date or CCV, the number begins with 2008.

You'd have to add appropriate logic to the cc_validation class script.
Or alter the cc payment module to skip validation if the card matches a certain pattern.

would you be able to tell me how to do this? the code is confusing to me.

I am capable of entering the code I am just confused on how to write the code (I have already tried and failed).

Also I just realized that I forgot where the validation script was located. Having a hard time finding it again (I was not looking for it when I found it last time).