I was trying to avoid that, did you file the sides or the teeth? The 10-42 cassette is really testing the chainline, it might be better to stick a chain catcher on.
You need to look at where it's catching. I took a fraction of a mm off the sides of the wide teeth one-by-one until it meshed smoothly.
@Chalfie started
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I was trying to avoid that, did you file the sides or the teeth?
The 10-42 cassette is really testing the chainline, it might be better to stick a chain catcher on.