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[Larz60+]

There's nothing wrong with making changes, it's the best way to learn.
I learned very early on (probably in late 1960's) when making changes, no matter how sure that you can do a dozen at a time,
only make one change, test to make sure it works as expected, and repeat until all twelve are done.
It will take less time in the long run, and will give you that warm fuzzy feeling that all is well!