No worries. You had the right to point out what you saw. I've looked at the thing quite closely before and can see why it's been negated in so many rebuilds (from reputable rebuilders). I followed their lead based upon my own study of these things. I suspect it was similar to the 2100 and 4100 which originally had open vents and due to EPA regulations had to have these vents "plugged" while at idle.