You did not say what control unit you have, but here a link that has Quicksilver controls. If you click on on of the models, there is a link to the schematic break down to the right of the pic. You should be able to get the PN and then search for the part at the best price.
http://www.marinepowerservice.com/Bo...nt_cat4=454210
Try to be more specific with your post. The more info the easier it is for these guys to help you out. Hope this is what you need, now if I can just find the tach harness I need to plug into my control unit.