Hey John...TT V8 setups are mainly for Factory Cars like Mustangs, Cameros, TA's etc...
For what you are looking at, you will probably need to build Custom Exhaust Manifolds for your Turbos. Being that you have a Small Block Chevy, header kits are $0.10 a dozen, so you can experment for very little cash output. If you are the welding type, you could build your own turbo manifolds.
The turbos in that photo you sent look like T-28's, which are small. They spool fast and create boost quick off the line, but they will kill your top end.
Do you know a lot about Turbo setups? If not, I would suggest the book "Maximum Boost" by Corky Bell.
www.amazon.com/exec/obidos/tg/detail/-/0837601606/102-2545352-4585750?v=glance" target="_blank">http://www.amazon.com/exec/obidos/tg/detail/-/0837601606/102-2545352-4585750?v=glance
Your local Barnes and Noble book store will have it in stock. It will give you a motherload of information on turbocharging.
If that is your Kelmark in the photos, that thing ROCKS! Nice ride my friend. By looking at the engine photos, it looks like there is a lot of room in the engine bay for "Hairdryers", but don't forget you will probably need an intercooler for the system also...
Here are some interesting things...
www.marineparts.com/partspages/Merc/merc3.htm" target="_blank">http://www.marineparts.com/partspages/Merc/merc3.htm
Good Luck and check out that book.
Bow
Going retro with my '91 Nissan 240SX