Meter reading conducted by gutless salesman is a con, sadly (8)
I believe the answer is:
scansion
'meter' is the definition.
(scansion is a kind of meter)
'gutless salesman is a con sadly' is the wordplay.
'gutless' suggests removing the centre.
'sadly' indicates an anagram.
'salesman' with its centre removed is 'sn'.
'sn'+'is'+'a'+'con'='snisacon'
'snisacon' with letters rearranged gives 'SCANSION'.
'reading conducted by' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for scansion that I've seen before include "analysis of verse" , "Rhythm" , "analysis of poem" .)