What a fun project! Imagine not only resurrecting a piece of history, and not only justifiably beating on it on the track, but also justifiably driving it through the mud and dirt. Fun times! There's only one way to find out what the NOS W-31 parts are worth -- put them on the market. I do know that in recent years I've seen a NOS '70 W-30 carb sell for over $1500 (if I remember correctly). I would expect the NOS intake to sell for about the same. Maybe the balancer will be in the same ballpark? One comment on the carb: its value probably depends a lot on its build date. What's the point of spending a fortune on the "correct" carb if its build date, clearly stamped next to the part number, is after your car's build date? So if it's a service replacement carb from, say, 1972 I would expect the value to drop no matter how pretty it is.
