Throne on show in large church not yet finished (8)
I believe the answer is:
cathedra
'throne' is the definition.
(cathedra is a kind of throne)
'on show in large church not yet finished' is the wordplay.
I cannot really understand how this works, but
'on' could be 'at' (I've seen this in other clues) and 'at' is present in the answer.
'church' could be 'ch' (abbreviation on maps etc) and 'ch' is located in the remaining letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for cathedra that I've seen before include "Ex ..., with authority of the Pope" , "When Pope speaks ex . . . . . . . ., infallibility is claimed" , "'Ex ..., with the authority of status or rank (8)'" , "seat" , "Ex ...; given by pope as infallible judgement" .)