Peace Mr. Popat,
To answer ur question, there is no concept of conversion in hinduism, therefore there is no prescribed system to which caste any prospective hindu would convert to.
Happyheart has his own problems that drives him to spread lies about hinduism. Dalits used to be considered achoots or untouchables in the past by some bigots, but now this is a crime according to Indian penal code considering someone achoot or untouchable. For ur kind information, Chief Minister of India’s most populous state Uttar Pradesh is a dalit lady, Ms. Mayawati is a so called dalit, our CJI Justice Balkrishnan is a dalit, the speaker of Indian Parliament Mrs. Meera kumar is a dalit. And the list is endless because we have a system of reservation in our government jobs for dalits.
Therefore U will find more than 33% dailts in all goverenment higher jobs. They are working as District Megistrates, Higher Judicial Officers and Police Officers all over India. Discrimation on cast lines is serious offence in India and one can land in jail for discriminating against a dalit. Read the following story, and there are thousands like it.
The Hindu : National : Three school teachers jailed under SC, ST Act
So the untouchability myth just boomrangs over here. However there are still some bigots who practise this social menace, but exceptions are everywhere.
Hope this clears ur misconception.