Looking for vin number

[Numplumb]

Hi all I have been searching the Internet trying to find a way of getting the vin number of the donor car that my engine came from so that I can get a letter from Mazda for proof of engine age, I found a post on an American site which states that the vin number is stamped on the oil pan, does anyone know if this applies to uk models as well as Miata models and where to find it on the sump.
Any help would be appreciated.
Regards Mick.

[Wain]

My VIN was stamped on the donor car chassis above the engine. I have never managed to find anything like that on the block other then the engine model number (i assume it is, as its only 4 characters).