SVG img drawing itself using scrollMagic

Hello,

I have creating an svg form layout that I want to appear to be drawing it self as I scroll down using scroll magic, as you can see from the example http://codepen.io/anon/pen/OyQZbq the right side is already there and as your scroll the left side appears but doesn't finish. I'm new to scroll magic and with out buying the draw svg plugin I don't know what tween to use, so any suggestions would be great thanks.