This article describes how to change the cartridge on a Eclipse Cascade faucets. The other Eclipse faucets are similar.
Cascade
This picture shoes the handle on the Cascade prior to starting.
cascade no plug
Remove the plug under the handle.
Cascade with Allen Wrench
Insert the Allen wrench that came with the repair Kit. Fit it into the set screw and loosen the screw. You can then remove handle.
Cascade with plug wrench inserted
Once the handle is removed insert the reverse plug wrench into the socket. You will need a adjustable wrench to loosen the retaining ring that is holding in the cartridge.
Cascade Parts
Once you remove the retaining ring the cartridge will come out. Replace the cartridge making sure the nubs on the bottom fit into the corresponding holes in the faucet. Reverse the steps to complete the repair.