Well at least Festus can read english. Glad to have you on my team! Let me try and explain myself more clearly.
"Match" is the defining word that limits the modification in my opinion, and it can be looked up in the dictionary for those of you who do not know what it means.
From the Websters Seventh New Collegiate, the definitions that pertain are, as a noun, (1,a) a person or thing equal or similar to to another, (1,c) an exact counterpart, (3,a) a process of matching, and as a verb, (3,a,2) to cause to correspond, and (4) to fit together.
Quickshoe,it would be very easy to tell if someone had gone too far. If you "match" them as Festus and I think it says, you would just remove the material necessary to line them up, remove the overlaps. This would mean that if one port is bigger than the other one all the way around, only the smaller mating port would be altered up to 1" from the manifold face to match the larger port. The originally larger port would be as cast and look like the rest of the unmodified port. If one port was offset from the other one, one port would be gound on one side and the mating port would be ground on the other side. The two unmodified halves would be as cast, look the same as the rest of the unmodified port. It would not even take any specilized tools, a visual inspection would tell, the same check that would be done for any other illegal porting.
17.1.4.D states that "no permitted componant/modification shall additionally perform a prohibited funtion". I would argue that raising the top of the port beyond that necessary to eliminate any overlap areas, the matching allowed by this rule, would be an illegal modification because it could effect the air flow to the valve due to the change in the angle of approach of the column of intake air to the valve head. I have a 2.0 Ford racing modification manual from Dave Vizard that shows how to raise the port roof at the manifold face for that exact reason. That possibility eliminates the interpretation that it is "free" within 1". "Match" defines what you can do and sets the limit.
ITANorm mentioned adding an "anti-reversion step" at the intake manifold. Sorry Norm, 17,1,4,D, illegal function, unless the intake ports had this funtion from the factory.
Oh, yes, "match" as a verb, (1,a) "to encounter successfully as an antagonist". A truly fitting definition of what we are doing here in the off season.
