An easy way to make photoetch pliable is to anneal it. Use a small torch, and heat the part till it glows red hot, then let it cool on it's own. When it does, the metal will have lost its temper, and will be very soft. You can now bend the part in any shape you desire. If you want to put the temper back into the metal when you're finished, heat it up again, and then dunk it in a bucket of cold water.
Note: While this works well on larger PE parts, I wouldn't suggest using this method on small, delicate parts, as you're likely to seriously deform the part with the application of heat. Should work well on armor skirts, but do it carefully, and don't overdo the heat.
