Any thoughts on this engine issue

Demon,

Did you indicate the timing is fluctuating? If it is then you need to find out why. If the diss is correct you should not be seeing any advance at idle. And I know you do not have any vacuum hooked up correct? So if the diss is not providing any advance at idle and there is not vacuum advance to deal with, then if the timing is moving around more than a degree or two at idle then something is not right. And keep in mind that you are only seeing what is happening at # 1 TDC.

I understand that everything is new in the engine, but unless you happen to have all bad carbs. All bad diss. All bad ECU's, Or have an electrical problem beyond any level of understanding, you need to look at what you do know. So is the timing moving around? If it is then something is not right.