The serial number tag is located on the SWIVEL BRACKET (port or starboard); or, check the INSTRUCTION PLATE, Positioned among the thumb screws above the steering tube. Thankfully, PartsVu has a wealth of resources to assist you find the Mercury outboard parts you need to maintain your engine running easily, https://alexispttrq.blogdemls.com/36784397/top-boat-marine-temperature-switch-secrets