He was the Assistant Director of the Commerce and Industry Department during the Hong Kong 1967 Leftist Riots and was involved in the anti-propaganda "war room" under Jack Cater against the rioters.

[3] After departing from the civil service, he was the director of the Hong Kong General Chamber of Commerce in which he held the position from 1975 to 1988.

[4] In the 1988 Legislative Council election, the second indirect election to the Legislative Council of Hong Kong, McGregor ran in the chamber's Commercial (First) functional constituency as a liberal candidate in the chamber for the greater democratisation against Veronica Wu who was supported by the conservative lobby Group of 88.

[8] On the eve of the end of the colonial rule, he was knighted in June 1997 along with Donald Tsang, the then Financial Secretary and later became the 2nd Chief Executive.

McGregor retired in Vancouver and was fond of golfing and gardening; he continued to keep track on current affairs in Hong Kong.