I think there might be numbers under the rear package tray also depending on what year car this is. (core support, dash or doorjam, package tray and trunk lip)

2003 Dodge 3500 Diesel

1964 Plymouth Savoy White 2dr sdn. 512 stroked, Dominator, New Best 9.75 @ 138.50mph
2019 Challenger Scat Pack 1320 White Knuckle-K&N Cold air filter, Billit Oil catch can, drag radials stock 11.911 @ 114mph