[jhv48]

You have a four corner adjustable idle circuit on your Holley 750. Try richening up the idle circuit about 1/8 of a turn on each screw (out).

My Demon (Holley Clone) exhibits the same stumble when rolling on the throttle slowly when the idle circuit is a little too lean.

Hope that is it. If not, check the float levels on both bowls. Should be at the bottom of the screw on plug's threads. Next will be the squirters. Both should begin to squirt as soon as the throttle begins movement.

Don't worry, it is something simple!