Larry-----
As far as I know, Mark IV engines built prior to 1968 were painted with the exhaust manifolds installed, so there should be evidence of paint, to some degree, on the exhaust manifolds near the cylinder heads. From 1968-on, there is some disagreement regarding whether or not the manifolds were in place during engine painting, but this would not apply to a 1966 model, in any event. If the 66 judging manual says that there should be no paint on Mark IV exhaust manifolds, I don't know why that it says that.
As far as I know, Mark IV engines built prior to 1968 were painted with the exhaust manifolds installed, so there should be evidence of paint, to some degree, on the exhaust manifolds near the cylinder heads. From 1968-on, there is some disagreement regarding whether or not the manifolds were in place during engine painting, but this would not apply to a 1966 model, in any event. If the 66 judging manual says that there should be no paint on Mark IV exhaust manifolds, I don't know why that it says that.