Its me again lol

So... if you haven't read my last post that's okay... it was long and a pain in the butt. I have a new issue that has arisen but I dont think it will be as difficult to solve. I hope. So here we go.

My engine is set to 12* BTDC I'm idling at 900 rpm, and my idle mixture screws are working. Now I'm get this nasty stumble when coming off idle to a light throttle. At WOT my truck charges ahead... but if I dont hammer it it struggles. The motor is making 14 -15 Hg at idle. I'll post video. My thought... and forgive me if I call it a wrong name, but i think my blades are sitting wrong and covering the " idle lean in" it's a term my friend used. The rectangular opening in the main bores that assist when when coming off a stop. I havnt pulled the carb yet, as I wanted some ideas before i go through and disconnect everything. But I think the last time I chem dipped the edelbrock 1406 I may have sat the blades wrong. Am I right on this? Or is there an easier fix I'm missing?