I repeated this process for the back of the armor.
But despite how well hot glue works, I decided to fasten the pieces together with my assortment of nuts and bolts. First I drilled a hole using my screwdriver and a machine screw. I would imaging any screw would do.
After a while, I added the second set of shoulder armor that I made a template for earlier. I bolted these in as well. My girlfriend then threw it on, with a helmet too!
It's a bit big on her, but cool nonetheless!