Hooker super comp 2118

I recently got a good deal on a new set of 2118 supercomps at a swap meet and would like to put them on my 67. These have the 1.75 inch primary's and 3 inch collectors. Are these headers a good fit on a 67? Any thoughts about the 1.75 primary's powerwise? My car had the comps with 2 1/8 primary and 3.5 inch collector when I bought it, but they are too rusty to reuse and seem a little large for my setup. The old headers had been "beat to fit" in a few places as well. The engine is a mildly built 396 with 781 oval port heads. I plan on using flowmasters with an x pipe and turndowns out of the mufflers.