Design adopted no good — accepted initially in the distant past (4,3)
I believe the answer is:
long ago
'the distant past' is the definition.
(I've seen this before)
'design adopted no good accepted initially' is the wordplay.
I cannot quite see how this works, but
'no' could be 'o' (O resembles 0) and 'o' is located in the answer.
'good' could be 'g' (abbreviation) and 'g' is located in the answer.
'accepted' could be 'a' (financial abbreviation) and 'a' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'in' is the link.
Can you help me to learn more?
(Other definitions for long ago that I've seen before include "Ancient" , "Very far back in time" , "way back" , "Many moons past" , "In the far past" .)