That's going to be a custom job (as most turbo systems are). You could possible take your exhaust manifold and flip it upside down. Do they make any sort of block hugger headers for the inline six? If so, maybe use one of those. It's certainly going to take some cutting and welding to get it done though. I would also assume that you're going to have to upgrade to a metal head gasket also. You'll be blowing head gaskets all day unless you go really conservative with the boost, and what fun is that?
Oops! I spoke too soon. I just looked up some pictures of an inline 6 and noticed how the intake and exhaust manifolds are set up. Flipping the exhaust manifold would put the turbo right where the carb is. Of course anything is possible with the right amount of money.