I don't know if it will work or not, I'm not a certified pep instructor, lol it just makes sense to me, to line the pieces up on the opposite cheek so they indent instead of bump out, and vacuum cleaner hose cut in half long ways is what they use for the chief helms,like the parts near his cheeks, and your CQB ridges look very similar, so that's my suggestion. although you may have to trim the indents a little if they bump in too much, but it doesn't look like it would be a problem. Oops, sorry for the double post, I didn't think it went through the first time...