Warning sign about endless trouble for well owners? (6)
I believe the answer is:
oilmen
'well owners?' is the definition.
'warning sign about endless trouble' is the wordplay.
'warning sign' becomes 'omen'.
'about' means one lot of letters goes inside another.
'endless trouble' becomes 'il' (I can't justify this - if you can you should believe this answer much more).
'omen' placed around 'il' is 'OILMEN'.
'for' is the link.
Can you help me to learn more?
(Other definitions for oilmen that I've seen before include "Businesspeople" , "crude workers?" , "riggers, perhaps" .)