Trans ID needed
I think the only negative is the scarceness of after market torque converters for the 19 spline input shaft. You can convert from 19 to 24. You need a 24 spline input shaft obviously & a reaction shaft support from '67 up. If you grab a later reaction shaft support make sure it has a narrow journal for the reverse/high drum bushing or you will also need a later rev/high clutch drum with the wide bushing