I think the most important thing is to first figure out what you NEED to buy - versus what can be reused. Also, depending on the condition of what you have and the experience/skills of your rebuilder, the parts list and specific combination of parts can change dramatically. Hopefully you have a rebuilder who is experienced in flatheads, has the necessary equipment (some of it is specialized - especially in the valve train area) - and knows how to use it. Once you know what you have and what can be reused, then talk to Mac, Red's Headers, Third Gen, etc. . . I'd stick with ONE supplier for everything - and not mix-match components from all over (since you're new to this).
Feel free to PM me once you have your ducks in a row - be happy to provide some perspective to what you're undertaking and things to potentially think or be aware of.
Best of luck and it is FANTASTIC that you're bringing an old engine back to life!
