After complaining to David about the ACS freewheel, he contacted them and they agreed to replace two of them. They told me that the two they shipped me had .004" and .008" run-out, both within spec., so Saturday I got busy trying to isolate my chain oscillation issue.
After replacing a noisy wheel bearing, I set me wheel in my home made test stand, sans freewheels. I placed my dial indicator on the left side freewheel threads and found .003" run-out on my hub. With the .004" freewheel in place (wrench tightened), it had .005" run out. When I clamped my freewheel tool in the vise and really tightened it down, this dropped to .003". I'm not happy with it but it's acceptable.
Next, I checked the output shaft and found no discernible run-out but when I checked the run-out on my dual sprocket, it came out to .015"!!!!! That's a big problem but I was unable to separate the track sprockets from the adapter to find the exact problem. I'll email David again.