rumblefish question for you?

Hi Rumblefish,
You gave me some good advice on a 318 build but sadly lost my notes.
I sware my dog ate it or my 2 year old daughter.
Looking for 300-325 horses fairly cheap. nothing wrong with more either.
One question should I reuse my 318 heads or get some later 302 heads if i can. Is their much benefit? Mine would need a rebuild no doubt.