Green’s Dictionary of Slang

admirably, enjoyably, well.

1901		Bulletin (Sydney) 3 Aug. 13/2: [He] props me ’ere in the eye, an’ I ’its ’im back with the leminade-bottle, an’ flattins ’im out lovely.
1915		H. Russell diary 11 June 🌐 Our artillery bombarded the German trenches blowing them about lovely, sand bags were flying everywhere.
1917		A.G. Empey Over the Top 143: Everything went lovely and it [i.e. a play] was a howling success.
1955		B. Schulberg On the Waterfront (1964) 242: A week ago I was doin’ lovely.
2012		‘Dutch’ ? (Pronounced Que) [ebook] [They] had caught one of the Harlem spots slipping lovely .