Hi Steve. I'm Greg, 10 years awarded Windows MVP, specializing in Installation, Performance, Troubleshooting and Activation, here to help you.
You wouldn't load the printer driver into a document, it's specific to the printer at the recipient's end so having it already loaded on their end is all you can do.
What makes you think the formatting will change if they choose to print it while choosing a size paper the printer is capable of printing?
So the answer is that there's nothing you can do with their printer driver on your end to assure the document you're taking care or provide in the necessary format will print for them. They have already done that by having a printer that can print it.
If I am not understanding exactly what you're asking, please clarify so I can help you better.
Feel free to ask back any questions. Based on the results you post back I may have other suggestions if necessary.
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