Part # 391-6790 for B body I also have the handle for part # 391-6789. The comp plus mechanism is the same for all 833's I think I have the short rods for A and B bodies too. Those would be extra.
$150 shipped for the shifter.
I run stock leafs and shocks, with a snubber. 4 speed. 340 in a 383 car. I know the torsion bars are thicker, thats why it drives so good. I wonder if the leafs are stiffer too? Would a softer leaf help the 60 ft?