The serial number / data plate on my 1915 roadster is currently mounted on a wood block under the upholstery of the "dummy" driver side door. Is this the correct location? The location doesn't make sense to me, since the only way one could see the data plate is if the side panel is removed. Since the wood has been replaced, I cannot confirm that this is the original, or correct location of the data plate.
The patent plate sat on the firewall originally, to the left of the coilbox and above the steering column, partly covered by the body cowl flange. The car number on the plate (lower than the engine number) was discontinued in may 1915 and the space for numbers was left empty until the plates were redesigned.
Here's a thread where John Regan gave an exact location for the screws: http://www.mtfca.com/discus/messages/29/6661.html
Thank you for the wonderful response. The information cleared up another question of mine. My patent plate has a lower number than the engine number, and I wasn't sure if that was correct. Now I know that it is correct.
New question: should the serial number on the title match the engine number, or the number on the patent plate? My title serial number matches the engine number.
Model T's were always registered with the engine number. That's probably the reason why car numbers were discontinued - they were never used.
Ford sold numbered engines as spares, that may be the reason why the two number series started to drift apart.
Yes the engine number should be the same as the number on the title.
When I registered my cars, I used the body number stamped into the floorboard riser of the '24 coupe and on the '14 I used the car number stamped onto the patent plate on the firewall, If I ever have to install a different engine in either car, the DMV won't know or care.
The number used will depend on what your state law says. My state law says if there is not a VIN , the engine number will be used as the VIN. Check your state web site.