In which Emirate is it the easiest to pass a registration inspection? Abu Dhabi, Dubai, or Sharjah?

Some context:

I bought an 80’s Mercedes and I want to fully restore it in another country and send it back.

To avoid double paying on customs duties, I want to ship it with UAE plates, do the necessary repairs, and ship it back.

To get UAE plates, I first have to get it registered. I’m on a bit of a budget for this project and want to do just enough to get it registered.

So the question is, in which emirate is inspection least thorough and why?