News to me: "Shed one's wedge"

A Guardian article on literature's Top 10 Unreliable Narrators (thanks, Chris!) includes this paragraph on Martin Amis's 1984 novel "Money":

John Self is one of literature's most repulsively addictive narrators. The book might be* subtitled "A Suicide Note", but it is in fact a love story, with Self dreaming up ever more extravagant ways to shed his wedge while pursuing entirely corruptible Selina Street, among others. The fact that Self might never have actually existed, revealed towards the end, is Amis's sly take on the death of the self.

Um, "ways to shed his wedge"? Sounds dirty, but that's probably just because of all the other phrases in which a guy is said to be X-ing his Y. My second guess was that it meant "commit suicide," as in "shuffle off this mortal coil." I figured the Internet would clear it up in seconds, but no -- the usage is surely there, but it's buried in heaps and heaps of wedge issues and golf wedges. Ditto for Nexis cites.

But yes, the OED has the answer, in a 1993 addition: A wedge is slang, originally criminals' slang, for "A wad of bank notes; hence, (a significant amount of) money." Among the citations is one from the Times of London, 1981: "Top villains ... share an idiosyncratic argot (‘wedge’, for example, for a stack of money)." Did the thin end of this wedge ever make its way into American usage, I wonder, or is it strictly a British thing?


*I would probably have written "the book may be subtitled A Suicide Note"; I'd be tempted to read "might be subtitled" as meaning "could be," but in fact, that is the subtitle.