Mopar 396 SB Stroker is off the Dyno & in the Books

a 3.79 crank is available for not all that much money

http://www.molnartechnologies.com/molnar-cranks.html

that just leaves the custom pistons unless there is some oddball chevy rod that would make this work with a piston intended for a 4"crank with a chevy pin.
no just use a 6.25 rod instead of the 6.125 rod.Simple!