This crossword No. 21766 clues and answers were published on Sat 11 Dec 1999 and the puzzle can be visited by following The Guardian Prize Crossword No. 21766 link.
All Across Clues and Answers:
1-across – H’s work at vice removal is affecting the brain : PSYCHOACTIVE
8-across – Small child holding a speaker wins the palm : TALIPOT
9-across – Holy person deserves to precede Eliot, the poet : STEARNS
11-across – Morning on film, going into Mexican port : TAMPICO
12-across – Grace in films became increasingly wet : RAINIER
13-across – Pester the prince : HARRY
14-across – Moderated and went on changing, keeping back eccentric : TONEDDOWN
16-across – H’s direction, its first part having got by : NORTHWEST
19-across – Do business with the wind : TRADE
21-across – One pound unit may be integral to the structure : INBUILT
23-across – Unquiet is the city, South American to North American : RIOTOUS
24-across – Droppings from an unknown create problem : EXCRETA
25-across – Roy, the golden beast of the prairie : ORBISON
26-across – Deceleration depends on gravity and air resistance : FALLINGSPEED
All Down Clues and Answers:
1-down – Royal resort between rivers in compound : POLYMER
2-down – Make over for heartless solvers, very quietly if you begin : YUPPIFY
3-down – Comforter in bed, consumption much exaggerated in space : HOTBOTTLE
4-down – Backwater for Irish and Norse gods : AESIR
5-down – Singular work of H getting hissed off stage : THEBIRD
6-down – H’s work naturally makes me turn green : VERTIGO
7-down – ‘Oly H, enemy of fashion, doesn’t lose 9, they say : STITCHINTIME
10-down – H’s work for arrogant interns, as composed : STRANGERSONA
15-down – Some note or notes on H’s work : NOTORIOUS
17-down – H’s 23 girl : REBECCA
18-down – Parasitic worm, caddish type, holding its breath? : HAIREEL
19-down – Time and money with 13 is H’s work : TROUBLE
20-down – Enraged maybe by diabolical road use : AROUSED
22-down – See 10 : TRAIN
This crossword has in total 28 where 14 are across and 14 are down.