Who told you that? - Most of the CAI setups for the SS I've seen retain the tank. The tank is the bottom of the air cleaner box. Some of the kits replace the upper portion, but many consist of just a larger piping to allow greater air flow. Is there something else being added at the same time that might require it, maybe a forced induction setup?
One thing to watch out for, replacing the down pip on the SS pretty much requires a tune, otherwise you'll be running dangerously lean on the top end.
Borla Exhaust, CAI, e-fans, Wester's Tune, MarkMc's lift & Z71 Shocks!