I started with a slight dripping problem(sayko system).i decided to replace all 3 stem assemblies together as they all were about 18 years old.after reassembling the new stems(danko brand),turned on the water supply & checked faucets.hot & cold worked fine but when the shower was turned on,water came out both the shower head & the bottem spout(and i might add fairly strong).any ideas?? and by the way all 3 seats were also replaced.i also tried all old parts & same thing occurs!! is there a special way the divertor valve should be installed??

A diverter stem assembly's installed the same way it came out. If you can't get the diverter to work a simple solution would be to replace your spout with a diverter spout and leave the valves diverter open. This is just a suggestion in case you consider changing out the valve. Regards, Tom