Matching Numbers on a car

I'm recently learning that having matching numbers on a car is a good thing. My question is what parts on a car have the unique identifier? B4 I change anything on my car I would like to know what parts have these unique identifiers. There is probably a post in here somewhere that someone can point me to.
Thanks. ;D

Engine and transmission. Everything else will just have a date code that corresponds to the time the car was built.

On the engine, is it the block, heads, carb, intake manifold, exhaust manifold, etc.?
Thanks for the input! ;D

Paul,
here is the post that shows where the VIN is stamped, on the back of the block.

http://californiaspecial.com/forums/index.php?board=1;action=display;threadid=1073

Doug

On my car it is just the block and transmission. I will eventually check the axle but I do not believe it will be there.

So there are not unique identifying numbers on each head, each exhaust manifold, intake manifold, carb, etc. Only on the block and tranny?
Thanks for everyone's help.
;D

If VIN stamping even took place it was usually on the engine block and trans only. Most of the time it wasn't even done.

All the parts you mentioned will need to have the correct date code to be considered authentic. At one point someone could have cracked a cylinder head and replaced it with a correctly dated replacement and not many people would be able to tell.

If you have an engine that didn't get stamped but the date code is within the range for your particular model that would be considered the original engine. You can see this creates a little bit of gray area as far as some FORD vehicles are concerned. Pity the GM car owner, the general stamped the engine, trans, and rear end religiously, "numbers matching" carries more weight when dealing with those cars.

To further go into the numbers thing, most Ford parts had casting numbers on them. They mixed and matched a lot of stuff from earlier models when possible, but always used the same items in a given year and model, unless there was a midyear change, and then everything after that used the new number. As an example they may have used a manifold from a 66 Fairlane (coded C6OE) and while a Galaxie manifold from the same year might fit (coded C6AE) it would be technically incorrect. For a 68 Mustang, anything with a C9 or above is obviously wrong, but it will probably work just fine. Without the big Ford book to tell you what is correct, you'll go nuts trying to get it all right.
Got you totally confused yet?
Steve