Go into the COMMAND PALETTE, choose the OTHER tab. Now also map the OPTION key to the Y key...then it should do what you want. I do this with the C command. I don't just want what I selected put in the clipboard, but I want it immediately put into the PREVIEW monitor. To do that you press ALT/OPTION-C. But I mapped OPT to C as well and now it does it with one push of the button.