The Illinois Administrative Procedure Act, as now or hereafter amended, is hereby expressly adopted and shall apply to all administrative rules and procedures of the Department of Revenue under this Act, except that (1) paragraph (b) of Section 5-10 of that Act does not apply to final orders, decisions and opinions of the Department; (2) subparagraph 2 of paragraph (a) of Section 5-10 of that Act does not apply to forms established by the Department for use under this Act; and (3) the provisions of Section 10-45 of that Act regarding proposals for decision are excluded and not applicable to the Department under this Act to the extent Section 10-45 applies to hearings not otherwise subject to the Illinois Independent Tax Tribunal Act of 2012.