Product Eligibility workflow custamization

Hi,

I have a requirement to customize Product Eligibility rules in Product Promotions based on the Contact information like (Contact First Name and Last Name). The present vanilla functionality checks the eligibility criteria based on the Account. Could you please let me know the process how to include the Contact based rules in the vanilla workflow. The below vanilla workflows which  I found. Also could you please let me know the Eligibility functionality and how exactly it triggers the rules based on Account/City/State/Postal Code.

Check Eligibility & Compatibility – Default

Product Eligibility & Compatibility - Default

Thanks in Advance for your help.