John,
You should have had a similar problem with the bushing which "usually" needs to be ground down at that point to fit. I installed the Edelbrock adjustable arms and they were manufactured to clear the tab. I agree with Dave that you probably should grind off the new arm to allow it to pivot freely.
My 2 cents.
Gene
Correct, the bushings I got from BMR had a flat cut on both
bushings.
