A young ass man with a trash can, strapped to the back
Of his ass so the rats can't chew through his last pants
from Eminem (Ft. D12) – Under the Influence Lyrics on Rap Genius
Meaning
Clint Eastwood wasn’t pulling the biggest roles back in his younger years — his breakthrough came in the series Rawhide when he was 30. The implication is that Clint was broke as hell in his 20’s, thus having to wear a trash can to keep his clothes whole.
Kinda like this (even if “trash can” rhymes better than “barrel”):

Similar to Clint, The Slim Shady LP didn’t drop until Em was 27, which is considered pretty old for a debut album. But we all know how things took of from there.
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