Section 64(d) in The Merchant Shipping (Examination Of Engineers In The Merchant) Navy Rules, 1963
(d)A candidate may take Part 'B' or that Section of it from which he is not exempted at any time after he has completed the necessary periods of qualifying workshop and sea service, provided he also takes at the same time the whole of Part 'A' of the examination or such subjects, if any, in that part, in which he has not already passed or from which he has not been exempted under (a) above.
