Where is a Whizzer's value?

New comer here...
Are most Whizzers complete Whizzer cycles or do most Whizzer consist of Whizzer motors on various bicycle frames? Is one or the other more valuable?

On a Whizzer consisting of a Whizzer motor on a bicycle frame, how much of the value is the motor? If a person, today, finds a Whizzer motor and then finds an old bicycle and mounts the motor on it, is it considered an original Whizzer?

The reason I ask is that many of the old Whizzers I have seen on the web are very rusty and it is obvious that many parts such as fenders, handlebars, seat, wheels, need to be replaced. If I had the ability, and I am not saying I do, I would rather restore the original parts. But with my abilities I would need to replace many old parts with new parts. How much can you replace and still call it an original restoration? What constitutes the soul of the original bike...obviously the engine and frame need to be original.
Whats your opinion?