While there are several identical characters that mean different things from model year to model year, the key to making a cruncher that dosent get confused is to have it use process of elimination in determining what set of parameters to apply to the specific VIN presented.
It appears that the American Classic cruncher gets hung up on certian characters, and decides, "ahh well this is a canadian truck, so we have to apply the canadian "key" to this VIN".. which is why it often cannot determine anything else other than year and London, Canada.
My '29 thru '56 VIN cruncher works by making the program verify 2 or more characteristics of the VIN before determining the approperate "key" to use. In the event two or more characteristics apply to more than one model year, it then checks for the position of those characteristics to see which model year the VIN most closely resembles. (which is why a 0 gets automatically inserted at the beginning of some VIN numbers)
This problem gets more and more complex the wider the range the crucher covers.. and in the case of American Classics cruncher, which apparently covers model years at least thru '73 as well as U.S. and Canadian numbers.. it can get real hairy.
The problem with having a question and answer session, like, "Click on the truck your vehicle looks most like" is that alot of these trucks may either not be stock when you get them, or might not be anything more than a cab.
Thats why I really want to be able to include stock truck images of trucks for each model year.. so if you just bought what the VIN Cruncher thinks is a '52 Chevy 3100, you can compare whats sitting in your driveway with the stock image the cruncher displays along with the text results.
If a human with resource material can determine the year of a truck based soely on the VIN, then a computer program, with that same resource material, can do the same.
