Nuts -- kilo taken into Texan town (5)
I believe the answer is:
wacko
'nuts' is the definition.
(I've seen this before)
'kilo taken into texan town' is the wordplay.
'kilo' becomes 'k' (phonetic alphabet: alpha, bravo, charlie etc.).
'taken into' is an insertion indicator.
'texan town' becomes 'waco' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'k' going within 'waco' is 'WACKO'.
Can you help me to learn more?
(Other definitions for wacko that I've seen before include "demented creature" , "Out to lunch" , "Nutter" , "nuts" , "Mad" .)