How to edit cart block content?

[pinksharpii]

In previous versions of Woocommerce we could use the PHP template hierarchy to override parts of the cart and checkout but that seems to no longer be the case. The documentation is unclear on how to make modifications to the HTML.
Ideally I want to change the column header that says "Product" as well as remove the product link, and display a custom field below the product title in my screenshot below. But I can't find how to do that.
I really don't want to convert entirely back to the old layout just to do these little changes.