You will need to either go to the IRS website or call them to get the proper form. I would try the website first.
My answer is of a general nature and should not be construed to be legal advice nor creating an attorney-client relationship. Carol Johnson Law Firm, P.A. practices in the area of Wills, Trusts, and Estates, Disability - with a particular focus on providing Special Needs Trusts for disabled children and adults.