I have asked the same question a number of times. Most authorities do not know the actual law for "historical vehicles" in Ohio. I did add seat belts to the back seat of my '23 and I do use a car seat / booster seats for my kids.
My guess is that they would get you on a child endangerment charge if there was an accident, even though the law says here says that I am exempt.
Here is a sheet that I put together for the State of Ohio:
Ohio Revised Code … Vehicle registration and Historical Vehicle code.
This information was pulled from the Ohio Revised code to help vintage car owners understand Ohio’s law.
For more information, search the Ohio revised code at:
http://codes.ohio.gov/orc/45134513.38 Collector's or historical motor vehicle exempted from equipment requirements.
No person shall be prohibited from owning or operating a licensed collector’s vehicle or historical motor vehicle that is equipped with a feature of design, type of material, or article of equipment that was not in violation of any motor vehicle equipment law of this state or of its political subdivisions in effect during the calendar year the vehicle was manufactured, and no licensed collector’s vehicle or historical motor vehicle shall be prohibited from displaying or using any such feature of design, type of material, or article of equipment.
No person shall be prohibited from owning or operating a licensed collector’s vehicle or historical motor vehicle for failing to comply with an equipment provision contained in Chapter 4513. of the Revised Code or in any state rule that was enacted or adopted in a year subsequent to that in which the vehicle was manufactured, and no licensed collector’s vehicle or historical motor vehicle shall be required to comply with an equipment provision enacted into Chapter 4513. of the Revised Code or adopted by state rule subsequent to the calendar year in which it was manufactured. No political subdivision shall require an owner of a licensed collector’s vehicle or historical motor vehicle to comply with equipment provisions contained in laws or rules that were enacted or adopted subsequent to the calendar year in which the vehicle was manufactured, and no political subdivision shall prohibit the operation of a licensed collector’s vehicle or historical motor vehicle for failure to comply with any such equipment laws or rules.
4513.181 Historical motor vehicles.
(A) As used in this section, “historical motor vehicle” means any motor vehicle that is more than twenty-five years old and that is owned solely as a collector’s item and for participation in club activities, exhibitions, tours, parades, and similar uses, but in no event is used for general transportation.
(D) …. Notwithstanding section 4503.21 of the Revised Code, only one model year license plate is required to be displayed on the rear of the historical motor vehicle at all times. The registration certificate and the historical vehicle license plates issued by the registrar shall be kept in the vehicle at all times the vehicle is operated on the public roads and highways in this state.
4513.071 Stop light. (Chevrolet started stop lights in the 1925 model year)
(A) Every motor vehicle, trailer, semitrailer, and pole trailer when operated upon a highway shall be equipped with two or more stop lights, except that passenger cars manufactured or assembled prior to January 1, 1967, motorcycles, and motor-driven cycles shall be equipped with at least one stop light. Historical motor vehicles as defined in section 4503.181 of the Revised Code, not originally manufactured with stop lights, are not subject to this section.
4513.26 Safety glass required for new vehicles.
(A) No person shall sell any new motor vehicle nor shall any new motor vehicle be registered, and no person shall operate any motor vehicle, which is registered in this state and which has been manufactured or assembled on or after January 1, 1936, unless the motor vehicle is equipped with safety glass wherever glass is used in the windshields, doors, partitions, rear windows, and windows on each side immediately adjacent to the rear window.
4513.261 Vehicles to be equipped with electrical or mechanical directional signals. (Optional for 1939 Chevrolet)
(A)(1) No person shall operate any motor vehicle manufactured or assembled on or after January 1, 1954, unless the vehicle is equipped with electrical or mechanical directional signals.
4513.262 Seat safety belt or anchorage units required.
(A) As used in this section and in section 4513.263 of the Revised Code, the component parts of a “seat safety belt” include a belt, anchor attachment assembly, and a buckle or closing device.
(B) No person shall sell, lease, rent, or operate any passenger car, as defined in division (E) of section 4501.01 of the Revised Code, that is registered or to be registered in this state and that is manufactured or assembled on or after January 1, 1962, unless the passenger car is equipped with sufficient anchorage units at the attachment points for attaching at least two sets of seat safety belts to its front seat.
(C) No person shall sell, lease, or rent any passenger car, as defined in division (E) of section 4501.01 of the Revised Code, that is registered or to be registered in this state and that is manufactured or assembled on or after January 1, 1966, unless the passenger car has installed in its front seat at least two seat safety belt assemblies.