I think I've got there. I had an answer for 1ac based in the definition but had to resort to previous posts in this thread for the parse so thanks there. I had a different answer for 4dn which still gave me the correct missing letter. Anyone else? Made my LOI 10ac a challenge. I note that the letter before in each modified clue was never a crosser. On purpose? Has made me a bit dubious of having got the end game exactly correct but I've based it on a fairly concise list that I found online.