Across:
8 Duck (-O-) found in chopped up (= anagram indicator) mince (mince = INCOME) (INCOME) – the contents of a packet (INCOME is the contents of a pay packet),
9 Conventional (ORTHODOX) alternative (OR-) to hot (hot), wild (= anagram indicator) (hot = -THO-) party (-DO-) for mystery man (-X) (ORTHODOX),
10 Reference (CITE) charts from architects (‘charts’ from ‘architects’ = iect = CITE),
11 Irish stew (DISH-) from Ring (-WASHER) (DISHWASHER) produced by one working in kitchen (DISHWASHER),
12 Temporary occupant (LESSEE) of port (port/left = L-) city in Germany (Essen) hasn’t finished (n) (‘Essen’ without ‘n’ = -ESSE-) engineering (-E) (LESSEE),
14 Making sense of (ADDING UP) a pudding (a pudding = ADDING UP) mix (= anagram indicator) (ADDING UP),
15 One of those taking a chance, on balance (TIGHTROPE WALKER), on The Wire (TIGHTROPE WALKER),
18 Look (DÉCOR-) at (-AT-) Oriental (east = -E) (DECORATE) paper (DECORATE),
20 Exhibited (OPENED) definitive book (Oxford English Dictionary = OED = O-ED) writer (-PEN-) has gone into (OPENED),
22 Two goals (DOUBLE) in school (BASS school of fish) (DOUBLE BASS) – one of which is to play in the band (DOUBLE BASS),
24 A meat substitute (TOFU) starter of tempeh (starter of ‘Tempeh’ = T-) mysterious flighty type (UFO) served up (= reverse indicator) (UFO = -OFU) (TOFU),
25 Dresden (Dresden = END-RSED) novel (= anagram indicator) about love (-O-) (ENDORSED) signed on the back (ENDORSED),
26 Tempt (ENTICE) man (gent) not opening (g) (‘gent’ without ‘g’ = ENT-) with diamonds (-ICE) (ENTICE).
Down:
1 Heard (= homophone indicator) you (‘you’ = ‘u’ = U-) spilled (= anagram indicator) wine (wine = NWI-E) over skinhead (head of ‘Skin’ = -S-) (UNWISE) with rash (UNWISE),
2 What you get with doughnut (HOLE in doughnut) that’s part of the course (HOLE part of golf course),
3 Teacher (HEAD-) with a number of gowns perhaps (-GEAR) (HEADGEAR) and mortarboards (HEADGEAR),
4 Characters in upcoming (= reversal indicator) business obsessed (‘busineSS OBsessed’ = ssob = BOSS) with big cheese (BOSS),
5 Local drunk (local ‘drunk’ = STEWED) in shapeless (= anagram indicator) tweeds (tweeds = STEWED),
6 Guards (guards/police = BOYS IN BLUE) the Dublin footballers (BOYS IN BLUE),
7 Small matter (MOLECULE) of spy (spy = MOLE-) changing (= anagram indicator) clue (clue = -CULE) (MOLECULE),
13 The volume of students (SCHOOLBOOK) carried to class? (SCHOOLBOOK),
14 Coming from the orchard (APPLE), spotted Arabian (spotted Arabian = dapple horse) losing the head (d) (‘dapple’ without ‘d’ = APPLE),
16 With nowhere to go way up north (ICEBOUND), heartless (s) ship’s officer (‘bosun’ without ‘s’ = -BOUN-) is found behind (= position indicator) church (Church of England = -CE-) consumed by the papers (I-D papers) (ICEBOUND),
17 Most of (l) the fleece (most of the ‘wool’ = WOO-), top, dress (top ‘Dress’ = -D-) and cast-off (cast off = -SHED) (WOODSHED) in the outhouse (WOODSHED),
19 Sorry (= anagram indicator) images (images = AGEISM) of old prejudice (AGEISM),
21 Consequence (EFFECT) of iron (-FE-) and carbon (-C-) found in baby salamander (eft = EF-T) (EFFECT),
23 Isolated without lost (‘isolated’ without ‘lost’ = iaed = AIDE) member of staff (AIDE),
24 Caught up (= reversal indicator) in Aristotelian (in ‘ariSTOTelian’ = stot = TOTS) nursery group (TOTS).