Calvin,
After doing some research, I think that it might be possible to accomplish this without resorting to EnumForms(). One thing I've noticed is that the number of forms returned by it is usually far in excess of the forms available to the user. I think that you can accomplish what you're trying to do by using GetForm() and SetForm(). This is a SWAG, however. I'd try first using GetForm() to retrieve the structure for the desired form, then SetForm() to with the return value to set it. The problem here would be retrieving the current default. If it's "Letter" then you'd simply have to retriving that, then the desired form, set the desired, then restore the default from the first call to GetForm().
George
Ubi caritas et amor, deus ibi est