Where is property situated ?
if property is in Bombay ,Calcutta ,madras then apply for probate of will
3) probate is judicial proof that will is genuine
4)enclose affidavit of one of attesting witnesses if there is no contest you would get probate on 6 months
5) then apply for mutation of property in your name
6) enclose latest receipt of payment of property taxes
7) grand mother death certificate