RE: YS 110FZ engine repair
You can mail it to them. I suggest making sure it is insured, UPS or Fedex can also track it.
Include a note of what is wrong with the engine, and what you would like done to it. Also include your phone number so they can contact you. Email addresses are not good for contact as they don't do much email.
Just leave a daytime phone number they can contact on.
Troy Newman
Team YS