Probably from an earlier mis-reading? It is simply too low, it is a prewar number on a car built postwar. Not possible. Original title would have been based on factory paperwork, so likely at some time title was misplaced and car was inspected and issued a new one, with a digit missed. If you have a good title, run with it and get registered...but it is not right. It indicates that your car must be a '41, Merc or heavy truck...If you can see the number on frame, dig around and look for the stars and at the area where the 99 and first digit should be separated by a short special dash...somebody has missed something.
In the old car game the above crops up on a regular basis... Case in point;
In the mid 1970's my brother purchased a really nice '37 Ford 4dr.. The car was reputedly an unmolested original.. One slight problem, it had hydraulic brakes.. '39 pedal assembly, '39-41 brakes... My brother was told that the car was a special order car that came equipped with the hydraulic brakes..
I told my brother there was no such car ever made, someone had modified the car... Once my brother makes up his mind, there is no changing it..
Fast forward to 1982... My brother moved to Idaho, the car had to be inspected in Idaho, serial number, etc. Turned out the frame number was correct for a '37, the tile number was correct for a '39, Hmmmm ?
It was obvious that someone had "married" a couple of cars together.. Of course my brother had no idea there was a serial number problem because he like so many other people had never had the need to check the serial numbers..
I have always figured that someone, way back in the past had "dug" an undocumented '37 out of a garage/barn, cleaned the car up, repairing it as needed, added the hydraulic brakes and then sold the car.. It probably went through several owners, with it's history overlooked each time it was sold..
My brother still owns the car...