Just reading the IVA manual and bit confused by the statutory plates section. It says you need

Name of manufacturer
Approval no. And/or build stage no
Vehicle identification number

Name of manufacturer and vin I get, but what is the "Approval no. And/or build stage no"?

Just leave it out, dont even have an empty line.

That part id for multi stage/modular builds, (i believe thats for things like vans/trucks that have a body/chassus made with a plate, then additional things like tipper units, or transporter bodies added to them once leaving the main factory.

Cheers. It's not very clear in the manual.

Just to add, my tester was convinced that you had to have axle weights on it too. I wasn't convinced, it was one of those open to intepretation things. I ended up not arguing the point as he let me off anyway.

IVA manual makes it very clear that weights are not mandatory.