What did the guy tell you to use instead? I've been down this road before and dish soap is fine for beat up thrift store records but it leaves a film if you don't rinse it good enough. The trick is a drop of plain unscented soap in a spray bottle with distilled water, then wipe it with a microfiber cloth going with the grooves not across them. If the guy put you onto a spin clean or some wood glue method, that's a whole different level of work but it does get results.