I'm a bit new to zen cart and I have been searching the forum but have not found a solution.

My client is selling tickets (easy enough) I have setup the basics and have no problem buying the ticket, here is my issue

They do not want to rely on the email invoice and would rather have the customer print the invoice they get after they slide their card (again that part is easy)

I need to make the invoice that displays after a customer slides their card and the invoice that displays look like a ticket, IE a nice image header and footer and some formatting to the page.

What files can I edit to make these small changes? Unless it is a major undertaking I only need the files to edit.

My alternative idea was to have a PDF document that the customer could download their ticket after they have paid for it, but for this I would need zen to create the pdf with a unique number. Has anyone ever done this or is that something major to do that is not supported

Thanks in advance for any help!