Camacho. I think it'd be a damn nightmare for Shakur to face a prime Camacho given how low his output is, and given that he doesn't have enough pop to hurt Camacho. Camacho was not a skilless hack like Teofima. Camacho 8-4 imo.
Prime Camacho would give Floyd and Whitaker a tough fight, let alone Shakur, who isnt nearly as good as those two. Camacho wouldn't beat Floyd and Whitaker, but he'd give them problems.