There are two ways to do twin turbos. Because they're "twins" that means they're both the same size. One way is to have one running off of each bank of the exhaust. The other is to have them running in series.
Theres no point in twin charge on these cars. You'd have the super pushing air into the engine and when it spun up enough the turbo would push more into the super and be restricted by the super's flow capabilities.
Not many people go super and turbo cept when theres no easy UIM fix like there is on our engines.