According to the MI state website:
To qualify for an authentic license plate, the vehicle must be:
26 or more years old
Owned solely as a collector's item
A vehicle registered with a regular historic plate or authentic historic plate cannot be used for general transportation. The vehicle can only used for participating in historical club activities, exhibitions, tours, parades, car shows, swap meets, and similar uses.
Fee: $35 -- Make checks and money orders payable to State of Michigan. Authentic license plate applications must be submitted by mail. Applications cannot be processed at a Secretary of State office.
Applying for an authentic historic plate
Owners need the following items:
A color photocopy, a color scan, or color photograph of the license plate (passenger, commercial, trailer, or motorcycle). Do not mail the actual plate. Personalized, government, law enforcement, manufacturer, dealer, in-transit repair, disability, and special purpose plates cannot be used as authentic license plates. If in doubt, check with the department before purchasing a license plate.
Proof of ownership, preferably a copy of the vehicle title
Proof of Michigan no-fault insurance (not required for trailers)
$35 -- make checks or money orders payable to State of Michigan