Naturalized Brit applying for UK passport

[Stormtrooper01]

Hello,

My father was born in Zambia to a British father and South African mother. When he moved to South Africa he joined the SA Navy and became a Naturalized South African. Is it possible for my father to apply for a UK passport or citizenship after being naturalized?

I'm asking this because I want to apply for a job in England. I qualify for a UK VISA but if I can get a UK passport it would be a lot better. I have all the documents needed on my grandfather's side.

Thanks.