Iq 1663

[hankir]

The wordplay can have more than 1 extra letter.

15. Oil producers in Highland room on headland (6)

23. Left tavern wobbling after mostly excessive condition affecting the joints (13, 2 words)

10. Site ruined after drunk pitched up (7)

25. Champagne belonging to woman, that’s something excellent (6)

27. Bread crumb of ploughman rolling over in chemical combination (5)

Thanks.

[Neveracrossword]

15 Bennes, oil producers. Ben, Scottish word, Highland word, for Room +Nes(s), headland.

23 Undulant Fever, affects the joints.

25 Fizzer, something excellent. Fizz+(h)er.

That should help a bit, maybe give some letters for the others.

[hankir]

Thanks NAC.
Both Bennes and Undulant Fever new words.
Thought of Fizzer but did not look it up.