Printing envelopes - changing the size envelope to non-standard?

[Kathy]

I have invitation envelopes that measure 5 3/4" by 8" and can't figure out
how to set this size in the envelop options.
I also tested using a larger size and my mailing address info is wrapping to
a second line in the print but not when I preview it. How can I prevent this?

Thank you,

 

[Mary Sauer]

See here
http://www.gmayor.com/changing_envelope_layout.htm