Dr. Lee, Just in case you haven't noticed on my posts in the 6.2 forum I now have a working tach driven by the ESS.
Turns out that the dip switches were goofy switched them back and forth a couple of times ended up in the 4cyl mode makes me think the dip switches were installed upside down.
Got 2400 rpm in 25ms so all is well, thanks again for the article it worked just as you described.
Merle