More than one top down in flash car (9)

I believe the answer is:

rollnecks

'more than one top' is the definition.

'down in flash car' is the wordplay.
'down' becomes 'neck' (both can mean to finish a drink).
'in' means one lot of letters goes inside another.
'flash car' becomes 'rolls' (Rolls-Royce).
'neck' placed into 'rolls' is 'ROLLNECKS'.

(Another definition for rollnecks that I've seen is " Jumpers".)

I've seen this clue in The Times.

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