I'll try to get a vacuum reading while driving this weekend. I backed off the timing because i think it was pinging under load but that may have been caused by the lean condition.
Don't fall for selecting using the 2" below in gear or splitting the idle vacuum in half. That's a good starting point, not a set in stone method to get the right one. The vacuum gauge and A/F meter will tell you. You can run a PV that is rated HIGHER than your idle vacuum reading. I do it all the time.
If it's got adjustable air bleeds, you can make some adjustments there.
There is a guy that has done some real extensive a/f tuning and testing over at slowparts... I'll see if I can find a couple of the threads
