Hey chap - seen this thread and have to say first and foremost I'm not an armourer and well done that man for working hard to get where you are.
I do however have a RT-Mod suit and it's built for the bigger trooper. I have 46" chest and it fits me well, the thighs were a problem and I ordered some Troopermaster thighs and have shimmed the rears to allow a good fit.
You can get this to work so don't stress - it just takes time and effort and patience.