When the prop has a little plate at the back that gets captured by the body halves. I will either glue in the post and drill hole in the back of the prop hub. Or, leave the post in the back of the prop hub, and leave a hole for it in the engine.
But having said that.... this is one of the lessons learned.
The paint, use light coats, let it half dry between coats. This will let it be much lighter in weight and not puddle in the flat areas. Give that a go next time.
Nothing ventured, nothing gained.
You're on the right track.