Four hours of grinding with a rotary file and finished off with a rotary grinding stone. The ports now match perfectly with the head and gasket. This port matching made a noticable increase in both

It will help greatly but much better if you can equalize the port sizes and match the gaskets and cylinder head as well............if there's enough meat in the cylinder head without going through into the waterjacket and you used solid copper gaskets, unless the ones you have there are bigger than the biggest manifold port, which looks unlikely!