I'm just about ready to install the manifold on the 396 for my son's 67 and have a couple questions someone out there might be able to answer. The manifold is a cast iron, square bore (actually 4 individual bores of 1.575 inches)-part number is 3866948-with HOLLEY and GM markings. I believe it is off a Corvette 427/425 from the late 60's. I only have the original manifold (396/325 spreadbore with Q-jet) as a reference. What is the appropriate carb for this manifold? I assume a vintage Holley...how about modern Holley or Demon?