Brian your head choice may be limited to what your pistons are made for. If they are made for a Yates head your choices are limited due to valve angle and placement.
With a custom header they fit pretty good in a fox.
My machinist recomended that too me. He was going off of similiar combos that he had dynoed. That was about 2 1/2 years ago. Now, we would try something in the 850-950 range, but.................I already have the $700 demon