Green’s Dictionary of Slang

1. to achieve, to accomplish, to succeed.

1994

C. Major Juba to Jive.

2. to earn money.

1982		Afrika Bambaataa ‘Planet Rock’ 🎵 You just keep ticking and tocking, working all around the clock / Everybody keep rockin and clockin.
1989		J. Morton Lowspeak 40: Clock [...] 5. to count money.
1993		Dr Dre ‘Bitches Ain’t Shit’ 🎵 Fuckin’ hoes, clockin’ dough up to no good.
2000		in W. Shaw Westsiders 21: Nine times out of ten when you’re clockin’ them ends / Everybody and they momma want to be your friend.