Possible Clues:

• Check money put into second trip on board
• Look at nicer suits in a new style
• Cruise isn't all at sea? Go over that with a fine-tooth comb!
• Doctor cures nits accepting I go over with a fine-toothed comb
• Closely examine — unit crises (anag)
• Examine rise in cuts planned
• Study made by special constable before suffering neuritis