If I remember correctly, I have pulled the cranks and just left the gears on. The crankshafts are not useable for anything but marine, unless you want to have the snout welded up, turned to the correct diameter, and a keyway cut for the timing gear.

It is a combination of two gears, one bearing, two spacers, and three keys. It appears the gears and bearing are keyed together, and that assembly is keyed to the crank with a single long key.