What would be the best Exhaust set up? Emissions aren't a concern, but keeping the noise down is important, not that it has to be silent and a little roar is aweful nice when you get in it....

What size of headers, exhaust pipes and then muffler or mufflers.....

We're talking about performance that is streetable here.

Duals, singles, turbo muffler, glass packs, what's the best combo for producing HP?

 

slp headers and y pipe, aftermarket 3" cat, and there are many good 3" cat back systems that are really good.
1 glasspacks went out in the 70s
2 true dual exhaust sucks cause it kills our already limited ground clearance.
3 and cheap turbo mufflers are exactly that, they don't flow very well and rot out in about a week.
hope this helps does anyone else have an opinion?