Custom code to packaging slips and physical receipts

[ShepleysButcher]

Is it possible to make custom code changes to packaging slips and physical pos receipts. I see you can edit the template for these but I’ve enquired with some people who do custom code and they say the changes that I’m looking to make arnt possible.

For the packaging slip I’m looking to add a section which was a amount the customer paid as a deposit (the split payment on the pos system) so it’s easy to see how much they have already paid and to change them that much less when they come to collect their order. I’m also looking for things like quantities and variations to be larger and highlighted so they are easy to see when putting up an order. As well as some other bits moved  about.

For the physical receipts I’m looking to have the order number at the top of the receipt and the split payment amount on the receipt for the older customers.

please could anyone let me know if these changes are at all possible or am I dreaming?