Are you scrapping the donor in order to get an emissions exemption? If so, the vehicle must have the engine in it when you scrap it and there is a form that must be filled out by the scrap yard for you. The car must have been titled in the last 2 years before you register your replica. These are commonly called crusher cars. It must be older than 1974 I think and there are 3 engine size categories that your new engine has to fit into depending on the size of the crushed car engine size. If you are just trying to get rid of want you don't want from a car you removed the drivetrain, etc from to use for your kit you can call any car scrap yard and have the title to sign over to them.