ok, it's defeated me. even with all your help i still can't get these last few (and i have a chambers, albeit an older edition). many thanks again for all help given:
7ac sugar in heartless attack (4) _ C _ G scag? but why? 14 ac lots of privileges, of course, firm rejected out of hand (6) _ U _ R O S i can only think burros, but no idea why. 7dn blue grass finally cut (4_) _ A _ _ 18ac old teacher docking marks for agricultural officer (7) A _ I S T E R amister? but is it even a word? 27 dn search in leith police force is mounted (4) S C _ R scar fits but i don't know why. SCUR makes sense but no such word?