I had a good builder in San Diego 20+ years ago, he was an aircraft mechanic by day. Now, I’m afraid you are going to have to come to Phoenix.
The guy I have been using these last years does excellent work and is a Pontiac enthusiast. Call Mike at 480 242-7899.
I had a horrible experience with a local reputable shop and since have talked with so many people about how bad engine shops are with vintage engines. It seems impossible to find a good one. So I am very happy I found Mike through our local firstgen club.