Ok, this one has been lingering around these couple of weeks. Might as well give it a try and make one for our selves!
The only challenging part of this customization is the fin. That you would need to scratch build it for more accurate results. Otherwise, the model kit is rather easy to build, you only need to combine Tallgeese I EW with Wing Gundam Zero Custom EW kit.
You can also do this with the old HG model kits, but the heat lance will not be available in that scale.
you will also be needing the heat lance that you can get at Ebay
The back also needs to be combined with the Tallgeese's backpack
refer to this post for more photos http://www.gundamkitscollection.com/2014/06/mg-1100-tallgeese-flugel-custom-build.html