Excellent demo!
In the interest of safety, put a "L" shaped rod thru the holes of each of the washers as you install them.
This will help keep them in place until you have them all in and when you remove the spring, keep them from causing any problem.
After removal, as you stretch the spring slowly remove the rod and the washers will drip off.. Reinstall them on the new spring the same way.
I only mention this since coil springs are a lot like women, get careless, and they will spring or lash out at you and hurt ya!
Drop the spring on the floor with unsecured washers in it and bad things happen
Stretched coil springs have a lot of energy stored in them.
Ray