I agree Ted.
About the you tube... He, Andrew Cross (I believe), says he is cheating using a new valve and had said that depending on your water quality and age of the valve, you could have to pry the seals and spacers out.
I'd like to see anyone pry a spacer out. They fit the hole fairly tightly and there is no space to get anything into to pry them out. You have to make a puller.
That's why Fleck has made special tools to remove and install the seals and spacers of the 3600 IIRC, 5600, 6600, 6700, the top piston on the 9000/9100 and other special tools for the 1500, 2500, 2510 and manual (no power head) 2500/2510 valves.
I sold a Clack WS-1 to a guy two weeks ago that had to make a tool to get his seals and spacers out of his 5600 a few months ago.
Clack has the same number of main piston seals and spacers plus 2 more seals and 3 more spacers for the brine piston; they got rid of the separate brine valve, it's drive wheel and the salt dose cams of the Fleck design.
And all those seals and spacers in the Clack come out as one piece in under 2 seconds with nothing more than a curled finger tip.
Andy's film took 9.47 minutes to replace the seals and spacers in a new and never used 5600.
From the time you by pass a Clack WS-1, it takes less than half that time with a Clack. There are no screws or bolts, plates, washers, separate brine valve, meter cable or power head to remove on a Clack WS-1. And the Clack has no Teflon coating on the pistons or brine valve or their stems to leak as Andy mentions happening on a Fleck.