What must a Shiite do to be considered among Ahlus-Sunnah wal-Jama'ah, similar to a disbeliever who pronounces the Two Testimonies of Faith?

The path to repentance and rectitude for someone who held beliefs contrary to Ahl al-Sunnah wal-Jama'ah, such as the belief in the distortion of the Qur'an, or the infallibility and intercession of imams, or the apostasy of all but a few Companions, is to abandon these beliefs and embrace the religion professed by Ahl al-Sunnah, which includes the Oneness of Allah, the veneration, love, and contentment with the Companions, the belief in the Qur'an's preservation from distortion, and building one's creed upon evidence from the Qur'an and Sunnah, understood according to the comprehension of the Salaf of the Ummah.