I'm working on getting a PayPal donation form set up on a website for a political campaign. Per FEC requirements, I need to collect the Occupation and Employer of each person donating. I've got my form collecting this data correctly, but I'd like it to get passed to PayPal using either the "Custom" field or the "Option" fields, as described in this doc from PayPal: https://merchant.paypal.com/cms_content/US/en_US/files/merchant/collecting_fec_required_donor_data.pdf
Any idea on how I can get this data sent over to PayPal so the Treasurer doesn't get incredibly frustrated?