429 or 460 will also work, and as a secondary benefit is 75 -100 lb lighter. I'm not sure about all of the acessory brackets, motormounts, exhaust, etc. The FE is a direct bolt in.
The 4bbl manifold will help a little, but the bigger difference in the 2 bbl and 4 bbl FE engines was the compression ratio and cam. If you are using stock exhaust manifolds, the flat sided ones, big bore exhaust won't help. You will need either headers or the old style cast headers, they were a part of the performance options on various models through the 60's. There is a book floating around, I haven't seen one in a while but they must be available in reprint. "Holman-Moody Ford Factory Performance Parts Book" or something like that. It lists all of the casting numbers for the Ford engines of the 60's even the hard to find special order stuff. It is an invaluable aid for FE junkies at swapmeets and junkyards.