From Memory, Turbo Technics did a twin Turbo version kit for the V8, but it wasn't intercooled and it ran rather hot....... they went for a bigger single blower and intercooler and got something that worked pretty reasonably, but cost / performance, it was a bit of a do-do, people got similar power from more conventional tuning, with less side effects.....
But that was twenty oddd years ago!
With modern Turbo-know-how, hybrid blowers, fuel injection and efficient inter-coolers, may be a completely different story.
So I dont know, really!
If you are lloking at an 'old' turbo conversion taken off a dead engine, then I'd be asking why it was dead!
If you are looking to do a brand new 'built' motor or conversion, then I'd be weighing up the sales blurb and comparing it to stuff in the reel-steel or PRi catalogue, then talking to some-one like Roland at ACR or the Turners.......