You posted two times the same link

Same Scooters:
https://www.imcdb.org/vehicle_477538-Hyosung-Prima-Rally.html
https://www.imcdb.org/vehicle_477538-Hyosung-Prima-Rally.html

https://www.imcdb.org/vehicle_1789965-Guangzhou-Peugeot-505-1989.html
https://www.imcdb.org/vehicle_2048227.html

https://www.imcdb.org/vehicle_2048199.html
https://www.imcdb.org/vehicle_1764398-Fudi-Explorer-II-2003.html

https://www.imcdb.org/vehicle_1917983-Ford-Transit-1966.html
https://www.imcdb.org/vehicle_1917982-Ford-Transit-1966.html

Both have a role and are different color, they can stay separated (especially with a "big" role)
Regrouping is more for background cars, or when the cars seem really similar (same color).

https://www.imcdb.org/vehicle_2045587-Cadillac-DeVille-Concours-1994.html
https://www.imcdb.org/vehicle_2045573-Cadillac.html

https://www.imcdb.org/vehicle_2045137-Hummer.html
https://www.imcdb.org/vehicle_887985-Hummer-HMCO-1996.html

Same:
https://www.imcdb.org/vehicle_1754426-Hyundai-Porter-1996.html
https://www.imcdb.org/vehicle_1754885-Hyundai-Porter-1996.html

Same:
https://www.imcdb.org/vehicle_2039691-Chevrolet-Silverado-GMT901-2007.html
https://www.imcdb.org/vehicle_2042719.html

https://www.imcdb.org/vehicle_2039696-Mercedes-Benz-G-Klasse-W463-2002.html
https://www.imcdb.org/vehicle_2042638-Mercedes-Benz-G-Klasse-W463.html

https://www.imcdb.org/vehicle_2042639.html
https://www.imcdb.org/vehicle_2039695-Infiniti-QX80-Z62-2018.html

https://www.imcdb.org/vehicle_2039694-Ford-Escape-U204-2005.html
https://www.imcdb.org/vehicle_2042637.html