I'm sure I've got the answers, but don't understand the wordplay with these three clues, please could someone enlighten me?
18 down: Dickens put into script rising eccentricity (5) DE_CE (deuce?)
39 across: Hide, dressed in a stiff cape, minus flat hat(4) ROB_ (robe?)
43 across: Leaving Western Region, wrangler expresses "Gee" on tangling of reins RENA_ (renal? from the anagram, but don't 'get' the definition.)