Still getting a little bit of pinging... light moderate acceleration, nothing on WOT.
Today I replaced the ACT sensor. Boy was the old one gunked up!
Still a little, but since I've reset the timing (again to 10° BTDC), cleaned the MAF and put in a new ACT, I'll unplug the battery - tonight to clear any fuel trim levels and start fresh. I suspect it'll take a couple of days of driving for the system to settle down and work.
What pinging there is now is very light...and from what I read, it's a fine balance to keep these engines at peak.... fun to work on though!