Eastern Fleet being shelled will swallow tax boost (7)
I believe the answer is:
elevate
'boost' is the definition.
(thesaurus)
'eastern fleet being shelled will' is the wordplay.
'eastern' becomes 'e'.
'fleet being' becomes 'leva' (I can't explain this - if you can you should give a lot more credence to this answer).
'shelled' indicates the central letters (the outer letters or shell are removed).
'will' becomes 'intend' (intending is a kind of willing).
The central letters of 'intend' are 'te'.
'e'+'leva'+'te'='ELEVATE'
'swallow tax' is the link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for elevate that I've seen before include "Put on a pedestal" , "Lift up or ennoble" , "Improve morally" , "Raise, exalt (in rank)" , "Raise up, hold aloft" .)