I emailed spike-it to see if their paint can be injected or not. If it can be it might be the way to go to get the right look.

I will try the 2 hot plastics colors at once idea but I am terrible dealing with one at a time right now. I need to get a hot plate or 2 if I am gonna do much of that. Using a microwave for it will be tough.

T-Shirt paint might work but that stuff has an odor for what seems like forever. Not sure if I can get all the color to stay translucent inside the egg though using it.