Chassis - Body Number match up

[Bigbird]

Got to thinking about my car's original identity.

As most are aware it has had an EK subframe fitted, but I noticed that the ID Plate on the firewall has the number FB-225 6431-A.

I know that the FB-225 is a model designation (FB Special sedan) but would the rest of the number denote or have any relationship with the chassis number on the subframe? and does the A denote that this body was created in Adelaide?

Does it also give any indication of build date or even if it was early or late production?

It's amazing, I have been around these cars for years, and have never paid much attention to these details, but now I don't think I could ever have enough.

[Cal]

The A is for Adelaide.

The 6431 means it's the 6431st built.

There is a way to determine approximate build date from the above data...............I think Steve J knows how

[Bigbird]

So does this mean that the original chassis number would have been FB6431A ?