Open up maple and re-test over and over? Pffft, make an origin finder!
I think this is my outdated one since I had so many revisions but I used to use it quite often. Pretty useful for hats, hairs, and custom emotes lol
Oh, and I had developed it with some help of a friend. There's some Paint.NET trick to get the origins and after calculating some differences from him getting the origins in Paint and loading them on the editor there were a few formulas to perfectly center the items as if they were in-game. Most people don't re-test using maple, but do the Paint.NET trick instead. ;P