Cool project. You're fortunate to have found a car that is fairly complete. The grilles, especially with the "legs" sicking out of the back are very hard to find. Took me a year, and still ended up having to graft some "squares" into it.
I'm running a 318 in the Demon, Crane cam, Performer, AFB, & 302 heads. In installed the 302s as much for the smaller combustion chambers as I did for the hardened valve seats. I'm pleased with the combination that I have. Even your 318 is an interim motor, suggest using a 340 spec cam, or close approximation, to help get the benefit of the 4bbl.
Suggest a good photographic record to help stay motivated and on track. Here's some of mine. Good luck with your build.
