I went with a something like this:
https://www.jegs.com/i/JEGS/059/7353/10002/-1 purchased new from a local Chevy dealer years ago. Went with an Eddy performer intake + carb and headers. Still going good many years and 100+K miles later.
For your 63, a set of ram's horn manifolds would be a nice match and probably less trouble then headers.