I created a new cart object with additional fields, and then tried to update the existing dynamic product detail page which had the dynamic add to cart (registration form) included already. I had to update a few fields, but thought that would be faster than starting from scratch. on the page with my dATC, I deleted the old cart object, and then added the new cart object via server behaviors/eCart/eCart Object
Not sure where to go from here. have I just made a mess by trying to save time?