So next I got started on some fine-trimming/sanding, and the place I decided to start was with the biceps.
I started here because they are pieces that I became worried about while trimming. Both ends of the larger, wrap-around bicep piece are extremely thin, and one of those ends becomes an important front-facing seam.
There was a lot of mold curve-back on the ends, so you are required to trim that off so the pieces fit together properly (sorry, no picture). Trimming off the curve-back limits the options you have for how this seam fits together, and also makes the clip slot smaller, which is a problem since you have to leave enough space for the clip to fit in the slot. Be careful here!
Also, when you trim off the curve-back the pieces loses length (top to bottom), which leave the smaller bicep piece a bit shorter than the bigger bicep piece, so I had to trim the larger piece a bit to make the lengths the same (no picture). Then I trimmed the rest of the bicep pieces closer to the guide lines (where they existed), and used my best judgement where there weren’t guide lines.
Then I peeled off the protective plastic and rough sanded with some 80 grit sandpaper.
I kept a bit of return edge on the top and bottom of the biceps.
Top:
Bottom:
Here is the front facing seam. It’s really hard to tell in the picture but I think it turned out pretty good.
TL;DR
I trimmed and sanded the biceps.