Manual tranny,and parts for conversion

I'm only familiar and comfortable with OEM. I've done a number of A833OD conversions and have been happy. A really nice street setup. With a 340 in a 74 Duster you have plenty of power. I'd start scrounging 74 Duster parts to do it. Pedals, bellhousing, Hurst shifter. Is your 340 a cast crank or neutral balanced?