But before you mail it, ask yourself if it is really needed. Folks tend to try to attach a lot of extra crap that the IRS ignores anyway.
Thanks. Familiar with that form but it restricts the type of attachment. I have a Section 266 election. I guess it does not hurt to ahead and submit with Form 8453 and see what happens- if anything I have a record of it. Have you use for attachments not listed on the form?