How can I use the same “precedent” in both letterhead and email?

We have a requirement that when our taskflow generates a particular precedent, the user can select whether it is a letter or an email. If it's a letter, it should pop into
our default letterhead template, if it's email, we'd like it to pop into the default email template.
Is this possible? If so, how do we go about it?

This isn't possible precedents are tied to a single application. You will have to maintain a separate Word and Email precedent.