Is there a reason you are going with the weiand as opposed to a edelbrock performer?
I almost went with that also but then read that the edelbrock ports were closer to my 318 tiny intake ports. I think it was because it was easier for me to use the felpro 1243 gaskets that were 2.08x 1.05.
I was worried about my small ports until I read this thread, now i have work to do lol and want the better of the 2 intakes.
I did gasket match the intake but did not remove the heads and do those ( I wanted to but was worried I might screw them up) now I know What to do and its no big deal by the looks of it.