What's the difference between Ford's 6.8 and 7.3 Godzilla V8 engines?

Ford's "Godzilla" V8 engines are some of the strongest gas-powered blocks in its lineup. How do the 6.8 and 7.3 versions compare to each other?
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Toyota Century Coupe Will Get A Gas Engine, And It's Likely A New V8

Evan Williams is an automotive journalist and mechanical engineering technologist with more than a decade of experience in the industry. He has written for the Toronto Star and AutoTrader Canada and ...