Need help on new rebuild

I have run both the four hole and the single hole gasket with a 800 avs on that manifold with no issues. That being said it does get thin on that corner always was a concern of mine. As to the throttle blades hitting the plenum holes I can’t help as mine are cut out of the manifold. I always would put the carb on and move it around on its studs and then work the throttle. See if it would hang up.