I habe 2 ideas, but don't do the second unless there's no other better solution offered.
1. Drop the kidney/butt plate a bit more. It looks like you could slide it down a little more to cover more of your butt. This would help remove a bit of the overlap of the back plate.
2. If nothing else works, even other suggestions that come in, you may consider trimming some of the top of the kidney. I'm guessing you're a little short for a stormtrooper. Hahahahaha. It's not uncommon for shorter people to have to trim down some of the parts to adjust height.
The catch is that once it's trimmed it's really hard to put it back on. That's why I said only try this if no one else has a better suggestion, or nothing else works.
Otherwise, you look great. It makes me want to jump up and finish mine.
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