Hi Lewis, it looks like Flow could work, however you can't use it only on a part of an object it is for warping an entire object.

So you would want to make an initial "backbone curve" running down the middle of your entire object and then make a new full length backbone curve for your target.

If you can post your .3dm model file I can see if it's feasible or not, if you want to keep it private you can e-mail it to me at moi@moi3d.com

- Michael