The aluminum block is an issue if the engine must be a 351 Cleveland. In that case my suggestion for whatever its worth is to contact Tim Meyer and work with him. If having a "pure" 351 Cleveland is not an issue, then contact Jim Kuntz of Kuntz and Company, he can use an aluminum 351 Windsor block (Dart, Ford Racing), with what ever heads you want. Tim can probably build such an engine too. Both of these folks are competent and honest. Jim Kuntz is famous. Recommending people to either of them has (so far) not put a dark shadow over my reputation. Dennis Quella (Pantera Performance of Colorado) comes to mind as well.
My reputation is important to me, I don't like making recommendations or endorsements to businesses or people whom I cannot trust to treat you well. It makes me look bad and causes you grief. Please understand that my "omissions" are just as telling as my "inclusions".
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