Hi all,
Im preparing a light colored sign for submission, I've cut the image out and plan on setting it on a solid color background for easy clipping when (hopefully) sold to client. My question is, what the best method on preparing the background for later clipping of the sign when you don't have much contrast?

Tested a few methods, black and white backgrounds, then attempted to use blending modes with mixed results. Also tried the magic wand tool at a low tolerance and "blend  if" without much luck. Know some photoshop but far from being a expert.

 Any help would be greatly appreciated. Thank you