No engine number

[Dualist]

I know I'm a very long way off iva and stuff but I've noticed that I have no engine number And as I brought the engine as it was with no car/donor what do I do.?

As the engine is modular (wankel if you didn't know) a friend said buy a new front plate (as that's where they are supposed to be) and make up and stamp a new number on it and I may get an age related plate if I have the receipt. Is that possible.?