You just don't want it registered as a recent year - since that will trigger a requirement for emissions testing. They will search for a non-existent ODB port and fail you. Northern VA has emissions testing - not sure if other parts of VA currently do. The old tail pipe exhaust sniffers are gone.
You also don't want it titled as a 1957 Porsche - as that will trigger high yearly personal property taxes (and initial sales tax).