68 slant six trans to 64 225 slant six

later trans in an early car is a special convertor as the 68's are too big in the snout to fit the small register cranks. Change the crank and your good to go. get a convertor changed to a small hub (internals are different too, spline count). Late engine to early trans is just a hub bushing. Then there is the Detroit B&T driveshaft to deal with....rebuild yours, pain free. with the push button trans or column shift park pawl.