If I knew I would tell you
But I don't
Maybe one of the machine shops or machinest can come up with that information
If not try E mailing Kieth Black and ask them
I've bought a bunch of thier early hemi crankshaft adapter rings to use late model torque converters on the early top fueler stroker cranks like your wanting to use
Do you have a late model B, RB or 426 Hemi crank to use to measure off of? I can provide the late model crank flange thickness if you need that
The part I would worry about is the distance from the back of the motor to the flywheel flange distance