Racing Fuel Systems

I had this 4412 circletrack carb come in, the owner complaining of stumble. The throttle blades were drilled with overly large holes and throttle blades fully closed at rest. I sprayed dykem to mark the edge of the throttle blade and removed the blades and shaft to find that the Transfer slot about .100 short of the leading edge of the throttle blade! Is this a factory defect or is this plate missing one of those little holes found below the T-slot?
I tried posting a photo but its' too large.
The other very odd thing is that the carb is brand new, classic finish, purpose built by a carb shop for circletrack racing and the body stamped 4412-3!
Is this a fake Holley? The throttleplate had no provisions for vacuum.
Thanks, Oj

Get some new blades and try it.

I measured the slots, they are .150; I measured the primary of a 750dp and they measure .190 and have that little hole.
I did swap the throttle blades, I had replaced the black oxide with stainless and thats when I saw how far away the T slot was. I replaced the base plate and have it hanging until I find a sawblade thin enough to make the slots deeper.

Cheap Harbor Freight mini files. Find a flat one that cuts on the thin sides, and take the flat side to the grinder to make it thin enough.