Title for car where engines are swapped

[Benson]

Question:

Suppose I buy an engine from a Hot Rodder. He keeps the title and gets a new title for his hot rod using the engine number on the title.

Now I have an engine with "his engine number" on it since he has the title.

Now I put the engine in my car or one that I just built from parts.

DMV titles it with the engine that I have.

Who gets to keep their car if the DMV notices the numbers are the same?