Rich, I just got back from a weeks vacation and thought about this again. This is a '90 FCS. Notice how the neck and body joined has a built in backwards tilt. This is with no shim. All of mine, ranging from '85 to '94, are the same in that regard. I'm curious if the new builds are like this or just a straight cut pocket/neck like 99% of all the other bolt on basses out there.
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This is the after picture. With the angle that was on the bass' neck when I got it the action was really high, I don't have a pic of the neck at that point, but it was lower than what is in your pic.