Hi Peter,
I am in the process of finishing my short deck Clevor engine. I purchased a Holley Dominator EFI system for it but have not gotten far enough with the build to start the engine. I will be happy to share my findings once we start the engine. It will likely be a couple of months before we start it.
There are a few manifolds available. I chose one made by Trick Flow. Because my build is a short deck Clevor, I had very few options. They have manifolds for Clevelands. I believe their manifolds can easily handle boost.
Mike