Upon his return to Indonesia, Say worked at the Copra Foundation, a government-formed regulatory body for copra farmers especially in Eastern Indonesia. By 1956, he had been appointed the body's head in Ende in Flores. The foundation was reorganized in 1958 into a network of smaller cooperatives, and Say established local units across Flores while moving his office to Maumere.
In Sikka
Prior to his return to Sikka, Say had befriended Constitutional Assembly of Indonesia member Paulus Samador da Cunha, of whom he was a distant relative and had studied together in Makassar. In 1959, Sikka's legislative assembly held an election to select a new regent (bupati), with Say backing da Cunha's candidacy. Their primary opponent was law practitioner Vincentius Bata da Costa [id], backed by influential local politician Jan Djong. Although da Costa won the assembly vote, the Ministry of Home Affairs in Jakarta opted to appoint the more experienced da Cunha as regent.
Say's leadership of the copra cooperative gave him significant political influence in Sikka, namely through patronage of businessmen, and magnified by the fact that copra was practically Sikka's only significant trade good. This led to some political conflict with da Cunha, which largely ended in 1963 when Say was summoned to Jakarta by Frans Seda, who sent him to Manila. In 1967, Say had returned to Sikka, where an assembly vote was being held to replace da Cunha. Say won 5 votes out of 17 cast, placing second, but like da Cunha before him he was appointed by the Home Affairs minister to serve as regent and was sworn in on 6 September 1967. His first term was to end in 1972, but it was extended to 1973.
During the 1971 Indonesian legislative election, Say, like other regional leaders, received an explicit instruction from the Suharto government in Jakarta to campaign and push for Golkar's victory by any means necessary. Say, likely due to his close personal connection with Catholic Party leaders such as Ben Mang Reng Say (his brother) and Frans Seda, opted against doing so and allowed all parties to campaign normally, and ordered the disposal of pre-voted ballots. The Catholic Party won the election in Sikka – the only region of Flores where it did so. Say was later reportedly scolded by Ali Murtopo, but Murtopo relented after a phone call with Seda. Despite expectations from local Golkar functionaries, with one claiming he would "run around town naked" if Say survived two terms, Say managed to secure a second term.
His tenure as regent ended in September 1977, when he was elected as a Golkar member of the House of Representatives representing East Nusa Tenggara.
