Thanks all! Yes, I’d tried adding to the front, not the middle. 31’s great: I’d even tried adding that very word in that very place without spotting that it made something...! I’m not sure I like 2: that sense of ‘race’ is marked ‘obsolete’ in Chambers and it would have been easy to slip that into the clue for better precision. But thanks for putting my mind at ease on these!
Diver - your O,E,L,V are incorrect. For 'top' think what number that would be, then a word for a male cat, then reverse them both. 'Enemy' is extra. Def is last word of clue. Answer is a surname, part of a set...
(If you're still on the wrong thread, diver) Your letters are right - law is the Latin word (3 letters) inside the obvious abbrev. for Sovereign (all backwards) def is an early version of 'pixel'.
...I've made a complete hash of this by trying to avoid confusion with all of the possible abbrevs - ER GR HRH etc - and, in any case, the word you need isn't an abbrev but an informal shortening (sorry!).
I posted a query but it seems to have got lost. I’m looking for help with 24. I have O,E,L and V, but can’t think of a relevant word. All the rest of the puzzle is completed. I hope everyone is keeping well - at least this has kept us busy during lockdown