Cryptic crossword No 3,751

Across

1. Extreme right replaced by variable number of hereditary leaders (8)
2. Utterly fashionable friend of Dorothy (2,4)
3. Flexible production increases national growth at first (8)
4. Caddie goes berserk in traditional Nordic style (6)
5. One stone brought back for lodge (4)
6. Bigwig briefly ahead of schedule (4)
7. Opera company departs, recalling Celia Cruz, perhaps (5)
8. Introduction of liquid sample of polyethylene macromolecules (5)
9. A swerve back out (4)
10. Napoleon's temporary dwelling in retreat accomplished (4)
11. Find without complete record (4)
12. Fit up spouse, removing last right to return (6)
13. Loud Glock shot after student expelled for expression of encouragement (4,4)
14. Tailless beast of burden turned up (4)
15. Broadcast rules for laying out duties on beer and 'baccy (3,5)
16. Newspaper wizard to get counterpart (5)
17. Sterilise wounds of side damaged on distant moon (6)

Down

1. Express road passage (6)
2. Team Nike formulated anaesthetic (8)
3. Somewhat overengineered German side (4)
4. Leer at topless dance (4)
5. Fraternity golf ring (5)
6. Most malodorous farewell set heads spinning (6)
7. Small fry left in window, perhaps (4)
8. Loaded a blow gun in chalet (8)
9. Long way round Spain in days of yore, put the wind up someone (5)
10. Salts discussed nocturnal services (8)
11. Ebbing and flowing trip regularly taken by stunted surrealist (5)
12. Finishes up under the thumb? (2,6)
13. Having key part of Coronation ceremony without king (6)
14. Auburn fuzz (6)
15. Change of course, on reflection (4)
16. Party clobber (4)
17. New Siamese cat hair trousers (4)