Shipping class or price on packing slip, not just shipping method

Hi!

For our website we use your plugin to create invoices and packing slips and it works great. With your added documentation I was even able to change the templates to make them appear in our own fonts and style. I love it! There is just one thing I can’t figure out.
I would love to not just see the shipping method on the packing slip, but also the shipping class. Would that be possible?

I tried changing the packing-Slip.php file in my child theme. I tried changing all mentions of shipping-method to shipping-class, but that didn’t work.

I that’s too difficult it would also be help full to just see the shipping price, because that would give us the same information we need on the packing slip. Would that be a possibility perhaps?

Thanks in advance!

The page I need help with: [log in to see the link]