That Mark V helmet is looking pretty good! Good progress on the chest too! If you're planning on using foam for extra detailing, I would recommend to use super glue or tacky glue as an adhesive. If hot glue is used, it could lead to uneven surfaces. For example, the bead of the hot glue won't lay flat and some of it will protrude from the foam depending on how you lay it. Unlike super glue or tacky glue. That's been my experience thus far.