Just use a driver's side exhaust manifold from a 1955-57 265 V8. They're available at swap meets, and they come up pretty often on Ebay at dirt cheap prices. The outlet is forward of the steering box and it eliminates the need to modify the steering or offset the engine. Unless you're planning to run full throttle all the time, that manifold won't result in a measurable power loss at any sane RPM on the street. I've proved that on a dyno many times.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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