Nice, Jim!
Another way to take up space in a bucket is sand plus a piece of plastic wrap. I will also use Gorilla Tape (clear) on the outside of a wooden object I am epoxy-filling to slow the leaks. It won’t stop the leaks, but it will slow them enough that the epoxy sets before too much escapes. And it turns off pretty easily, even when epoxy-saturated.
Also, epoxy almost always takes more dye to color it than I initially think. Maybe two times out of ten do I put in more dye than I should have, three or four times I get it right, and about half of the time, I put too little, even knowing that I usually put in too little dye.