Glad to hear you were able to bend the tab back, and get it to run well, thanks for letting us know the outcome.
I wish I had thought to tell you to examine the balancer and crank sensor wiring before you had to buy the ICM, but it is good to have that new one, if anything put the new one on, and hold on to the old one as a spare for possible future troubleshooting.
When you replaced your plenum did you replace the LIM gasket as well, they are known to fail, they have an aluminum framed gasket that I recommend replacing the old plastic one with, unless you already replaced that old one with the aluminum framed one.
Also the upper intake manifold kit should have had a reduced diameter EGR Stovepipe, I hope you replaced the old one with that, it helps solve the problem you mentioned from the EGR gasses.
2006 Pontiac Grand Prix GT with SC
1996 Buick Park Ave NA