I finally took the time to dig in and properly fix my VUK. I knew it was an alignment issue because even at max power the ball was often stuck in the chute, and at best would trickle out. I am posting what I did to fix mine in hopes of helping others with the same issue.
Stern's fix-it bulletin was somewhat helpful by showing which screws to remove, but that's it. They offered no guidance on what distance to adjust the bracket and I don't think they can. This is a case-by-case thing that requires individual fine tuning. You can see in the photo how far mine was off from where it needed to be. Way off. Anyway, I was able to try different positions by securing the bracket with gorilla tape and then test firing. Once I located the ideal position I screwed it down and removed the tape. The whole process only took about 10 minutes. I probably stared at it and pondered for longer than it took to fix. I believe this is the only way to be sure before making new screw holes in your playfield. Also, when the positioning is correct you don't have to make the shooter tip concave as others have recommended (although I don't think it would hurt), or add tape, or anything else.
I am thrilled my Elvira finally plays as it was designed and got the GC score on my first game post-fix, with multiple trunk multiballs.
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