Green’s Dictionary of Slang

(Aus.) to work as a confidence trickster’s accomplice.

1952		Coast to Coast 1951–1952 199: My mother laughed: Siddy might have been ramming for you, but what you didn’t know, my lad, was that he was helping me to hook you. You were a goner from the start .
1964		H.P. Tritton Time Means Tucker 33: A gentleman with an umbrella, three thimbles and a pea was demonstrating how ‘the quickness of the hand deceives the eye’ and was raking in the money at a great rate. When business slackened, another gentleman would pick up the pea with surprising regularity. This would bring the crowd back to try their luck again. No one seemed to wake up to the fact that the second gentleman was ‘ramming’ for the first gentleman.