These simple homemade tools have worked well for me.
To De-moon, I use a once fired .50 BMG Cartridge case.
The case mouth is the perfect size to fit over the .45 ACP case. The oversize case body makes a nice handle. A few moments with a dremel and file creates the lip on the case mouth that levers the spent cases out of the moon clip.
To Re-moon, I use a simple wooden tray.
I took two pieces of 1 X 6 lumber and clamped them face to face. Then took a 1/2 flat bottom wood bit and bored a series of holes on the center line where the boards meet. Spaced the holes on 3/4 inch centers. Then separated the boards, used a table saw to cut a slot where the extractor groove & moon clip will pass and finally glued a piece of non-skid rubber on the back. I now have two re-moon trays that each hold 24 rounds.
Just lay the cartridges in the grooves, snap the moon clip on the first cartridge and sort of roll it down the line. Works great. Only things I'd change if making them over is to use a harder grade of lumber and bore the holes a bit deeper so that the bullet doesn't hang off the edge of the board.