Wait a minute... If you are going to rebuild it anyway, D3VE heads are great to use! After some basic port work, that you could probably do yourself, you just need some flat top or pop-up pistons to increase compression. That will save you a lot of money in the end, and work quite well....$50 bucks for both heads is what I would pay here, in Canadian dollars!
Can someone post that link with the head work on the D3's??? This should help you decide. You will like the 460; all it needs is the 1970 or 71 timing set (which are all over in aftermarket) to bring valve timing back from the dead. (It was a factory 'trick' to pass emissions, but it killed power)
Headers and 750 cfm carb will make you smile, without touching the heads!
Mark


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