Next to impossible to reach. The emblems I have on the spare front clip I've been covering in the Dash FAQ thread have three posts & nuts on the backside. With everything stripped out of that engine bay, it was still only easy to get at the front two nuts. The rearmost on each side are extremely difficult.
I decided to wait until I have the fenders cut off to get them the rest of the way off. I was thinking about retrofitting a couple emblems onto the Queen Anne's Revenge, but after that ordeal, I decided against it.
Good luck man, if you come up with a trick, be sure to let us know.