Need some advice

I would put a cable operated aftermarket floor shift in it just because its easy straight forward and affordable /available. you'll also need a radiator with the trans cooler or an external trans cooler. You could leave the clutch pedal setup in it and just "floor" the clutch pedal. That would leave provisions to switch it back to manual. Youll ned a flexplate Oh and kickdown linkage for the throttle at the carb and I think that's about it.