The New York State Police's position is that the rifle must remain in its original configuration with all 50 year old parts. I called FFLs after speaking to the NYSP and they told me they'd have to have Colt verify that all the parts were at least 50 years old. That seems to be the hard part. Colt does have a serial # lookup for the receiver, but who knows what happened to the rifle over the past 50 years.
NYSP dont make the law