I wonder if this can be used to bypass some new requirements of "new" vehicles if you use a donor car that is a little older.

Trans 131.03(12)
(12) RECONSTRUCTED AND HOMEMADE VEHICLES. Any nonexempt vehicle registered as reconstructed
or homemade under s. 341.268, Stats., shall be inspected for compliance with requirements applicable to
the model year of the vehicle as indicated on the vehicle's registration documents, unless the owner both
requests that the vehicle be inspected by engine year and provides a completed MV2588, exchanged
engine certification form, to the waiver investigator. In addition, the vehicle owner shall locate the engine
number on the engine for purposes of engine year verification by the waiver investigator.

Also I wonder how you become "exempt". From what I have been reading the requirements include, emissions testing via obd2, safety inspection so you need airbags, wipers, headlights, mirrors, brakes, etc.