How to transfer ownership of ancestral property?

We have plot of Agricultural land which belongs to my grand father near Hosur, Tamil Nadu. My Grand father, Grand Mother, both of my parents are passed away. Myself and my brother are legal heirs. We are planning to divide the property and register equally between myself and my brother. We have below documents. 1) Father Death certificate. 2) Mother Death certificate. 3) Legal Succession certificate of my father, mother, myself and my brother. 4) Death certificate of my grand mother. We dont have death certificate of grand father and we tried to search through taluk/district registry, but could not find it and authorities issued "Non Availaility" certificate. With these can we register the documents under our name or still we need to get grand father death certificate and their legal succession certificates? Please suggest.