It's in lib/WeBWorK/ContentGenerator/ProblemSets.pm, lines 248--259. If you reverse @nonGWsets and @gwSets in line 259, so that it reads
@sets = (@gwSets, @nonGWsets);
@sets = (@nonGWsets, @gwSets);
That should resolve the issue.
WeBWorK Main Forum
Which source code file must modify to make exams appear ABOVE homeworks in the list?
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