I know what you mean.
One of my 101s is registered with a casting number as the engine number. I tried to get it changed with the registration department. They refused to acknowledge their error and accused me of changing the engine. It all got too hard so I walked away.
And, my brown Mercedes, they changed to black on the rego info. So I just shut up about it.
I'll confirm the chassis stamping location tomorrow.
Unless otherwise stated, this post is the opinion of Mick_Marsh and should be read accordingly.
Hybrid SIII Stage 1 cab on a RRC chassis