In 1904 he gained employment with the Post and Telegraph Department before leaving in 1907 to join the staff of an accountancy firm in Ashburton.

[3] As chairman of the Harbour Board he oversaw an upgrade in the port facilities to accommodate larger sized ships.

In 1944 he was finally able to convince the government to allow plans to be prepared by the Ministry of Works which eventually lead to the construction of the Lyttelton road tunnel.

[1] In both 1950 and 1956 he stood as the Citizens' candidate for Mayor of Christchurch but was defeated both times by Labour's Robert Macfarlane.

While on his way to a meeting he collapsed in Tramway Lane and rushed to Christchurch Hospital where he was declared dead on arrival.

Many tributes were given at the funeral and at that week's city council meeting all highlighting MacGibbon's community service and contributions.

[7][8] The city council decided against either making an appointment or holding a by-election to fill the vacancy caused by his death and his seat remained empty until the scheduled 1962 elections in October.

[9] MacGibbon was appointed an Officer of the Order of the British Empire, for services to commerce and local government, in the 1952 Queen's Birthday Honours.