So I've been doing a lot of thinking and more research and pretty much throwing the reverse-flow idea out. Not that it couldn't be done, I just don't have the R&D budget any more. I'm still buying a new (to me) block and building a new setup for my '87 SPG. My questions follow:

Which would be better, a hybrid (dual vane) turbo or a sequential set up? The factory setup generates massive amounts of lag and I would like to do away with this. I understand that to get the benefits of a hybrid turbo I would need to go with an equal-length header. This would remove my AWESOME exhaust note (like a Subaru but actually nice to listen to) and I'm certain I would rather not do such. I have no experience with a sequential turbo system.

Can yous guys school me on the benefits/issues/ROI on both hybrid and sequential turbocharging systems? And maybe offer suggestions/advice on which direction I should take?