Hey Jeff! Congrats on beginning your build! I might have missed it, but who made your armor?
Also, I can't see any of your pics. Is it just me? Would love to see them!
There are many vertically challenged troopers out there (myself included at 5'4" and 110lbs!), and we can all tell you that sizing down a kit to fit well is possible! Nice thing is that we end up with lots of extra material for ABS paste (always good to have on hand, ask me how I know...).
Others are correct about how the armor should feel when it's on. Not too loose, not too tight. If you're smaller in the middle, you can add foam to bulk things up (along the back and kidney are common). You'll see as you fit your armor what looks proportional to your body. Study the screen grabs of troopers to get an idea of how it's all supposed to look. This one is one of my favorites:
My thighs were the most challenging to fit because they were so large to begin with. I have about 1/2" of room all around on them, and they don't wobble or rattle too much.
As always, be sure to wear your undersuit when sizing your armor! Everything fits much differently with the undersuit on. Looking forward to seeing your build!