Re: felt 1903
Welcome to the forums.
If you are a bit more specific you will probably get a bigger response. The 1903 is a great bike. However if you haven't built one of these before I would recommend starting with a cheaper steel frame bike and learning the in's and out's on that. You can always transfer the motor to the 1903 when you think you have it figured out. The Felt 1903 is an aluminum frame and it will require custom motor mounts that take this into consideration.
Knowing a bit more about your mechanical ability would help. Have you ever had to fabricate your own parts?