Well this has to be hypothetical as Toney won't weigh 168 lbs again until around 2 weeks after his death but if they ever did fight at 168 I'd say a UD for Calzaghe.

Toney is a tough son of a bitch and a skilful fighter but he was weight trained at 168 lb even in his prime.

He knocked out Michael Nunn in a terrific come from behind victory but he never really did much else at the lighter weights.

Tough fight but Calzaghe would outwork imo.