Actually, there are certain advantages to running twins, you can run two smaller turbos, and *******ly eliminate turbo lag.
The two-piece intake isn't gonna like it though. Should swap for an M1, or Hughes Air Gap.
Gonna need some way to supervise fueling as well. You could go with a two, or three-bar MAP system, but, you better have a 96 or newer truck to make programming easier. Other alternative would be some variety of standalone system.
I would stick with 7PSI or less on a stock motor, with a buncha miles on it. In fact, I would be tempted to run around 5PSI, just to get things dialed in, and then see about bumping the boost.
Thing is, this isn't going to be 'cheap' by any stretch of the imagination. JUST the electronics and such to enable it to run is going to be nearly a grand. Plus, you are going to need custom exhaust manifolds for the turbos....... and I haven't seen them in the aftermarket at all....... Hope you have some really good fab skills..... and a deep wallet.
Welcome to DF.