Pushing on them real hard just so we can have the big fun
He’s saying that they were scheming on the women with the biggest asses — and pushing up on them (‘pushing up’ on a girl was a term in the 80’s for approaching a woman. i.e. ‘I pushed up on it’ to mean, ‘I went to go talk to her.’). So Tip was pushing on them hard, with the actions possibility leading to sex or “big fun”.
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