Swapping 1964 plymouth Vailant from automatic to 4 speed

I assume Brewers has given you what you need to know whether you use stock '64-6 parts, or, convert to the '67-up stuff. It's possible that your crank isn't machined for a stock pilot bushing, but, that will depend on the crank used. If it's a 273 forged crank from an automatic, you'll need to either drill the hole to the correct size, or, hone it smooth and cut down a bushing to fit. If it's a 318/340/360 crank that isn't machined for a pilot bushing, just use a Magnum pilot BEARING. Naturally, you'll have some floor/hump work to do. Have fun!