One way to locate address in most letters — located correctly (6,4)
I believe the answer is:
'one way to locate address' is the definition.
I can't judge whether this defines the answer.
'most letters located correctly' is the wordplay.
'most' means to remove the last letter.
'letters' becomes 'post' (letters in the mail or post).
'correctly' is an anagram indicator.
'post' with its final letter taken off is 'pos'.
'located' anagrammed gives 'talcode'.
'in' is the link.
Can you help me to learn more?
(Another definition for postal code that I've seen is " Mail-sorting key".)