Good score on the motor...I believe pre '72 440's had the higher compression. Ie, non smog motor. You have any idea on the internals?? Start looking NOW for headers if you're looking for a deal. Hawk the classifieds section....every once in a while some BB A'body headers pop up...but go very quickly. Unless you got 700-900 to drop on new ones....
The BB A'body thing adds up quickly....everything needs addressed. Conversion Mounts, BB Xmsn, Rear End, Torsion bars, Manual brake conversion, possible manual steering conversion, Gonna need to cool that beast....on and on. I dove face first into it and figured out it's much more expensive than a simple small block upgrade. Cheers buddy!