good effort - not made it easy for yourself by having yourself behind yourself...
But it looks like you've gone round with a hard, fairly large brush which has is noticable at the full res size, either a softer brush to feather the merge, or more accurate selection (magnetic lassoo tool is my tool of choice), would sharpen this area up greatly.
for posting the full res, as it gives a chance to have a close look and see where you can improve, this issue is not noticable on the small size posted in the thread.
Great idea though, and this type of image, done well, I really love. Love to see you give it another go in one of the coming weeks!