The early, pre 1961 Mopar V8 of all sizes had a lot longer crankshaft distance and bolt pattern to the rear crankshaft flanges from the rear main bearings, 8 bolt hole with studs in the flywheel or converters and no converter and flywheel centering ring on the backside of the crankshafts to locate the converter or flywheel.
The early converters and flywheel slip over the outside of the crankshaft flanges and center off of them
Dang them engineers anyways ,