smudge42: The hints refer to French Eagles captured by British Regiments during the Napoleonic wars. Capture the flag should be obvious now, and Haforn is an Icelandic eagle, hence the cache name - sorry, I couldn't resist.
Murray Locomotive refers to the steam engine developed for the Middleton railway named after the battle of Salamanca in 1812.
PR2 8AB is the postcode provided by the Museum of the Queen's Lancashire Regiment for satnav users. The Eagle captured by Ensign John Pratt is stored there.
'Cuckoo' refers to the phrase shouted by Sgt Masterson as he captured the Eagle at Barossa, "By Jaysus, boys, I have the Cuckoo!".
Styles or Clark? - There is some dispute in historical circles as to who exactly captured the Eagle of the 105e Ligne.
55.949071,-3.194415 - the co-ordinates should take you to a pub in Edinburgh named after Ensign Ewart who captured the 45e Eagle.