Contact the Fusiliers Museum, which in this case the 5th Fusiliers is possibly Alnwick Castle, in Northumberland. They may be able to give advice on his Service Records or where to access them. But also what Regimental Histories are available for you to read. At that period of time with no major conflicts happening I would assume that on leaving Dover Castle, the likes of Gibraltar, India, South Africa and other British Garrisons would be on their list of destinations.
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