Want to have to remain outside yet heavily involved (4-4)
I believe the answer is:
knee-deep
'heavily involved' is the definition.
(as in being knee-deep in something)
'want to have to remain outside' is the wordplay.
I cannot really see how this works, but
'want' could be 'need' (needing is a kind of wanting) and 'need' is present in the answer.
'have' could be 'keep' (keeping is a kind of having) and 'keep' is found within the leftover letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'yet' is the link.
(Other definitions for knee-deep that I've seen before include "Deeply involved (in something)" , "(Of water) over the top of one's wellies?" , "Submerged to one's patella" , "Immersed up to the patella" , "Heavily involved - up to leg joints?" .)