Getting to the rear turbo is a LOT of work. That is why you dont see many over the counter intake upgrades directly to the turbo's. Can it be done, sure.
The above kit does have some functionality but it is not easy on the eyes. If one were to move the coolant reservoir and Wastegate boost tanks that may be a more ideal place for the filters.
And OP, Stett CAI is one filter. The reality is if you want big power, go single turbo. If you want every last drop out of stock turbo's or upgraded stock frame turbo's then an upgrade like(posted by boostede90) this may grab a few more ponies.