638 cid Big Block in a 69 CST/10 Shortbed

[bhunt31]

I'm wanting to build a Big Block for my 69 CST/10 and badge everything up like a 396 to fool the untrained eye. I'm looking at a Dart Big M block that is capable of 4.625" bore and 4.75" stroke. I'm wanting to keep a mild cam in it and iron heads so it runs and looks close to a stock engine. Preliminary runs on my Dyno program comes up with around 750lb-ft of tq@2K RPM and 502hp@4500RPM. The question I have is: has anyone done anything close to this power range in one of these pickups and what has to be done in ways of rear end, transmission,...etc. to handle this kind of power? Also, if anyone has any parts suggestions to stuff in this engine, please advise, remember I want to keep it stock appearing and idling.