Should be a piece of cake to make 600 HP with those type of parts. Here is my engine that is similar to your combo without the cleveland heads and just about 50 less HP
http://www.roushparts.com/pdf/427R.pdf
Mine is not installed yet but don't forget about all the other upgrades that will be needed now or in the future for the increased HP
Better cooling system
Larger fuel tank pick up
Half shafts
Rear billet axles & bearings
Brakes
Chassis Braces
The list never seems to end!
I'm sure George and the other members will have specific information on your questions, but looks like your on right track for a solid engine build.
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