Mumbai, April 15: Salim Merchant of the music composer duo Salim-Sulaiman, who has put together the music of the stage musical show 'Disco Dancer-The Musical', has said that he and his sibling were clear from the start that Bappi Lahiri's original music for the eponymous Mithun Chakraborty-starrer film 'Disco Dancer' would be retained for the musical.