I couldn't find legs, abs, or lower back, so I took what I found and put them all together in one file and added the abs, legs, and the details of the lower back. I'm going to use foam for the other parts including the calves, knees, and the main part of the lower back. I'm a bit bigger in the chest than you skinny guys, so I added some chunkiness to the chest, hopefully with room to spare. I also added cutouts to slip a belt through the ab plate for easier rigging. I've scaled this to my height 6'2", and I wanted to post it for anyone who wants it.
I would give credit to the original modeler of the parts that I used to start with, but I suspect it's just an edit of the game rip. The helmet may be original since it's more detailed than the game file. Sign your pep files guys! :P
(the box at the bottom is there for help in scaling)
Download it here. Not unfolded yet.