Twin Turbo set up for BBC

I've got a 454 tall deck that I'm wanting to do this to.  I don't want to supercharge because this makes MORE than enough low end torqe to spool up two 88mm turbos.  Does anyone have any recommendations as to places that I can look to possibly find a set up for a big block?  Websites that I may be able to look at?

I know that I would like to find a pair of exhaust manifolds to use that are flanged to work with the right sized turbos.  This engine will start out at a carbeurated motor and then eventually I'll turn it into an EFI.

Currently, I have a stroker kit to make the 454 into a 540.  Dished forged pistons, a comp cam 294/300 duration, wanting to run this into 5" exhaust, and keeping the motor at about 8.5:1 ratio to work with the turbos.  Any suggestions would be MUCH appreciated.  I'm trying to find complete kits as opposed to trying to piece one together.