"Hell no! What do you think I am? "I'd never do something like that. Aw shit. Aw hell. The poor old fella. Wait a minute – " he says, training his eyes on me suddenly. "Where were you?""Somewhere else," I say. (22.125-26)
Earl's definition of manhood can be seen in what he will and won't do. He's deeply offended that Jacob thinks for a second he'd participate in redlighting Walter and Camel, saying "What do you think I am?" This is not just about masculinity but about who he is at his core. The implication is that a good man would never do such a thing.