Simplify the following text for a Grade 6 native English-speaking person.
Original: After convincing his troops to accept the principles , which were promulgated on February 24 , 1821 , as the Plan of Iguala , Iturbide persuaded Guerrero to join his forces in support of the new conservative manifestation of the independence movement .
Simplified: They are known as the Plan of Iguala . Iturbide then persuaded Guerrero to join his forces in support of the new independence .