I do this along with the strapping to keep the forearms, biceps and shoulder bells as "one whole piece" XD Just some simple gaffa tape.
I saw someone do this on one of my troops.
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For a better way to do this though, I'd recommend SImpixel's thread on crafting a bicep strap hook with just scrap pastic.
http://www.whitearmor.net/forum/tutorials/article/37-howto-create-a-bicep-strap-hook/