Choosing pistons

Evan, dome pistons and small chamber heads are backward for a turbo

The less Scr you have, the more boost you can run. The more boost you run, the more power you can make.
Sooner or later, the looooow Scr will become a problem off boost.
So for a streeter,the trick is marry enough off-boost Scr to still be able to start and drive the beast on a beer-run. The engine will then be the limiting factor for boost cuz sooner or later boost will bust the block.
I gotta tell you tho, that a well-tuned 360 with 400/450ponies, in a street A-body with appropriate supports, is an awful lot of fun. There are NO tires that I could install in the stock wheelhouses that will withstand that power in first gear at LEAST.With enough gear or rpm,I can spin them to over 60mph.
So I gotta ask the obvious; Since you are building a 408, you already have enough torque to do that in an Imperial! So what's up, that you want to boost it?

Getting back to those chambers. With boost, you can run almost any chamber, and use the top of the piston to be a part of it.
A D-cup is commonly used, cuz that's what is commonly available,for supercharging.
Commonly;for Normally Aspirated engines; Domed pistons are for racing, Quench-domes are for streeters with open chambers, and Flat tops for closed chambers;Commonly.