Hi Alex. Beautiful truck you've got there. You had limited experience with carbs so you jumped in with a supercharger and duels!! That is how you get'er done! LOL..

A couple questions for you. First you said, "I have an AFR gauge installed, and it was reading very rich (i.e.: saturated at 10.0) under load. I have adjusted the carburetor main and secondary jets from 68 / 76 to 64 / 72. For the most part, this looks to have leaned out the motor correctly. all eight carburetor idle mixture screws are set at 1 full turn out." What does "leaned the motor out correctly" mean? And at what rpm?
The mixture screws are for operation at idle. So we're talking about 2 different tasks. Also how is your AFR installed?
Has the blower maker offered any help or guidance? Or have you even asked them? And I'll end with this last question, at what elevation are we talking about? Sea Level?

Sorry for all the questions, but it's info we'll need to know.