I called Arizona Speed and Marine and they have control over 8 larger injectors in their 5.7 kit. They read the boost levels via a 2 bar MAP system. "Spark and fuel management system consists of a preprogrammed, plug and play ECU that works with the factory installed ECU to maintain all the manufactures emission and sensor controls."
ASM 5.7 Hemi Aftercooled Supercharger System
I asked him about a 6.1 system and he said he was in the process of putting one together for a customer but was going to limit the boost levels to 5 psi or so because of the 6.1's higher compression.
All in all I was very impressed by his (Jims) knowledge of the 5.7 / 6.1 engine.
He mentioned that the 5.7 intake has some kind of restriction (he went into detail but I forgot the specifics) in it that could really hamper the ability of fuel (or nitrous) to distribute evenly throughout the intake, thus making the larger injectors (or direct port for nitrous) the way to go.
He said the 6.1 intake does not have the same restriction.