That's not going to work then. You get a text area field, and two custom fields of name/quantity.
For 60 fields, you will want to use an IPN solution. You'll have to insert their information into a database first, then send the order to PayPal, then PayPal will return a validation code which you can then use to activate their account in the database.
Not terribly difficult but time consuming if you haven't done it before. Try
www.paypaldev.org and you may find some help or even premade solutions.